Apparatus and method of energy efficient illumination using received signals

ABSTRACT

Illumination sources are turned ON and turned OFF in response to detected levels of illumination in an ambient environment reaching respective thresholds, which may be user set. The detection of these turn ON and turn OFF events is verified, for instance against expected events or conditions for the particular location, date and/or time. An alert or log entry may be generated if a detected event or condition appears to be invalid. For instance, if an amount of illumination in the environment is different than predicted by a threshold amount or if a time that the event occurs or is detected is different than expected or predicted by more than a threshold amount. A level of illumination may be decreased to some non-zero level after a specified time after turn ON, and increased at some specified time before turn OFF. Use of information from external sources (e.g., satellites, cell towers) may allow times to be using local time, including daylight savings if applicable.

BACKGROUND

1. Technical Field

The present disclosure generally relates to the field of illuminationdevices and, more particularly, to control of illumination to improveenergy efficiency and security.

2. Description of the Related Art

Energy conservation has become of ever increasing importance. Efficientuse of energy can result in a variety of benefits, including financialbenefits such as cost savings and environmental benefits such aspreservation of natural resources and reduction in “green house” (e.g.,CO₂) gas emissions.

Residential, commercial, and street lighting which illuminate interiorand exterior spaces consume a significant amount of energy. Conventionallighting devices or luminaires exist in a broad range of designs,suitable for various uses. Lighting devices employ a variety ofconventional light sources, for example incandescent lamps, florescentlamps such as high-intensity discharge (HID) lamps (e.g., mercury vaporlamps, high-pressure sodium lamps, metal halide lamps).

There appear to be two primary approaches to reducing energy consumptionassociated with lighting systems. One approach employs higher efficiencylight sources. The other approach selectively provides light only whenneeded.

Use of higher efficiency light sources may, for instance, includereplacing incandescent lamps with florescent lamps or even withsolid-state light sources (e.g., light emitting diodes (LEDs), organicLEDs (OLEDs), polymer LEDs (PLEDs)) to increase energy efficiency. Insome instances, these higher efficiency light sources may present anumber of problems. For example, florescent and HID light sources take arelatively long time after being turned ON to achieve their full ratedlevel of output light or illumination. Such light sources also typicallyhave a high energy consumption during warm-up. Many of higher efficiencylight sources emit light with a low color rendering index (CRI). Forreference, sunlight has a CRI of 100 and represents “ideal light” whichcontains a continuous spectrum of visible radiation. Low CRI light isless pleasing to the human eye. Surfaces illuminate with low CRI lightmay not be perceived in their “true” color. Low CRI light makes it moredifficult to discern details, often requiring a higher level of outputlight or illumination to discern details that would otherwise bediscernable in high CRI light. Further, higher efficiency light sourcesmay require additional circuitry (e.g., ballasts) and/or thermalmanagement techniques (e.g., passive or active cooling).

Providing illumination only when needed can be achieved manually by auser of the lighting system, or automatically by a control mechanism.Automatic control mechanisms generally fall into two broad categories,timers and environmental sensors. Timer based control mechanisms turnlight sources ON and OFF based on time. The times are typically userconfigurable. Such relies on the user to account for changes in lengthof day light which may occur throughout a year. Very often, timer basedcontrol mechanisms are set once and never updated. Environmental sensorbased control mechanisms sense light or illumination level and/or motionor proximity. Light or illumination level based control mechanisms arecommonly referred to dusk-to-dawn sensors. Dusk-to-dawn light orillumination level based control mechanisms turn the light sources ONwhen a level of light or illumination in an environment falls below aturn ON threshold, and turn the light sources OFF when the level oflight or illumination exceeds a turn OFF threshold. Light orillumination level based control subsystems advantageously automaticallyaccommodate changes in length of day light throughout the year. Motionor proximity based control mechanisms (e.g., passive infrared sensorbased) turn light sources ON when motion or proximity is detected.Motion or proximity based control mechanisms turn light sources OFFafter some period of time if no motion or proximity is detected duringthat period of time. Sensitivity of such motion or proximity basedcontrol mechanisms is typically user configurable, as is the durationbetween turn ON and turn OFF. However, motion or proximity based controlmechanisms have limited range (e.g., 10 meters), limiting the number ofapplications in which such may be effectively employed. Motion orproximity based control mechanisms may also be ineffective where theambient air temperature or temperature of an object is close to that ofthe trigger temperature (e.g., temperature of human body). Some lightingcontrol mechanisms employ both light or illumination level based andmotion or proximity based techniques. Such lighting control mechanismsturn light sources ON only if motion is detected while the level oflight or illumination in the environment is below the turn ON threshold.Thus, the motion or proximity sensing is active only between dusk anddawn.

Sometimes these approaches are incompatible with each other. Forexample, the relatively long time for florescent light sources toproduce full output hinders the effective use of such light sources withmotion or proximity based control mechanisms. Further, many controlmechanisms are built into the luminaire. Such makes it difficult or evenimpossible to modify operation of the control mechanism beyond somesimple user settings (e.g., sensitivity, duration between turn ON andturn OFF).

New approaches to improving the energy efficiency of lighting systemsare desirable.

BRIEF SUMMARY

As previously explained, lighting systems which use dusk-to-dawn controlmechanisms typically provides light at a continuous, relatively high,level from dusk to dawn. The exception to such appears to be when motionor proximity based sensing is included in such a control mechanism. Inmany instances, a high level of lighting or illumination is notnecessary throughout the entire period. For instance, in retail businessor corporate office parking lots high levels of light or illuminationare typically only useful into the late evening hours (e.g., 10 PM or 11PM) and early morning hours (e.g., 4 AM or 5 AM). High level lighting orillumination between the late evening and early morning hours providelittle benefit. A lower level of light or illumination during such hoursmay achieve sufficient illumination for some desired purpose (e.g.,security), while reducing energy consumption. Such may useful with asimple dusk-to-dawn control mechanism. Use of a low level lighting orillumination during such hours may also make practical use of relativelyslow warm up light sources with motion or proximity based controlmechanisms since the illumination sources may only need to be warmed upfrom an already turned ON, but reduced output state, instead of warmingup from an OFF state.

Illumination systems may be used in secured environments or insituations where security is important. Thus, it would be particularadvantageous if the lighting control mechanism of the illuminationsystem is designed to handle unintentional conditions, for example thefailure of a component such as an ambient light sensor. It would also beparticularly advantageous if the lighting control mechanism of theillumination system is designed to handle intentional tampering, forexample tampering in the form of shining focused light on a light sensorin an attempt to prevent illumination of a surrounding area by thelighting system. It would additionally be advantageous if the lightingcontrol system continued to operate as programmed even if a componentfailed, for example even if a light sensor failed. It may further beadvantageous if the lighting control mechanism did not require extensivetraining, learning or adjustment to the existing ambient environmentalconditions. For instance, it would be advantageous if the lightingcontrol system could quickly adjust to the daily cycle (e.g., solarnoon, solar midnight) for the particular geographic location at whichthe illumination system is installed, without the need to first obtainsamples over multiple days or even weeks. It would be very advantageousif the lighting control system automatically determined the local timeof day for a particular geographic location at which the illuminationsystem is installed. Such would allow lighting levels to be programmedto coincide with local activity such a retail store business hours. Suchlocal activity typically occurs at fixed hours, regardless of the lengthof day or seasonal changes in length of day. For example, it would beadvantageous to turn the lighting system to a high level of illuminationat dusk, and reduce the output to a lower level of illumination at afixed time of day (e.g., 10 PM local time).

A method of operating an illumination system including at least onelight source and at least one controller may be summarized as fromtime-to-time, detecting a level of light in an ambient environment;comparing by the at least one controller the detected level of light inthe ambient environment to a first threshold; validating by the at leastone controller a result of the comparison of the detected level of lightin the ambient environment to the first threshold with respect to atleast one expected condition; and adjusting by the at least onecontroller an output of the at least one light source if both thedetected level of light in the ambient environment at least satisfiesthe first threshold and the result of the comparison is valid withrespect to the at least one expected condition.

Validating a result of the comparison of the detected level of light inthe ambient environment to the first threshold with respect to at leastone expected condition may include: comparing by the at least onecontroller an actual time at which the detected level of light satisfiedthe first threshold to an expected time when the level of light ispredicted to satisfy the first threshold for at least one of a currentlocation or a current date; determining that the result of thecomparison is valid if the actual time at which the detected level oflight satisfied the first threshold is within a second threshold of theexpected time when the level of light is predicted to satisfy the firstthreshold for the at least one of the current location or the currentdate; or determining that the result of the comparison is invalid if theactual time at which the detected level of light satisfied the firstthreshold is not within the second threshold of the expected time whenthe level of light is predicted to satisfy the first threshold for theat least one of the current location or the current date. Validating aresult of the comparison of the detected level of light in the ambientenvironment to the first threshold with respect to at least one expectedcondition may include: comparing by the at least one controller thedetected level of light in the ambient environment to an expected levelof light for at least one of a current location, a current date or acurrent time; determining that the result of the comparison is valid ifthe detected level of light in the ambient environment is within asecond threshold of the expected level of light for the at least one ofthe current location, the current date or the current time; ordetermining that the result of the comparison is invalid if the detectedlevel of light in the ambient environment is not within the secondthreshold of the expected level of light for the at least one of thecurrent location, the current date or the current time. Comparing thedetected level of light in the ambient environment to an expected levelof light for at least one of a current time or a current location mayinclude comparing the detected level of light to a value indicative ofthe expected level of light for the current time at the currentlocation. From time-to-time, detecting a level of light in an ambientenvironment may include continuously receiving a signal at the at leastone controller from an ambient light sensor which is part of theillumination system, the signal indicative of the level of light in theambient environment. The method may further include receiving a locationsignal at the at least one controller indicative of the currentlocation; and determining by the at least one controller at least one ofan excepted level of light or an expected time at which the level oflight is predicted to satisfy the first threshold based on the currentlocation identified by the location signal. The method may furtherinclude receiving a time signal at the at least one controllerindicative of the current time. Receiving a location signal indicativeof the current location may include receiving the location signal from aglobal positioning system receiver. Receiving a location signalindicative of the current location may include receiving the signal fromat least one cellular communications system receiver. Adjusting anoutput of the at least one light source if both the detected level oflight in the ambient environment at least satisfies the first thresholdand the result of the comparison is valid with respect to the at leastone expected condition may include turning the at least one light sourceON if both the detected level of light in the ambient environment isequal or less than a turn ON threshold and an actual time at which thedetected level of light satisfied the first threshold is within a secondthreshold of the expected time when the level of light is predicted tosatisfy the first threshold for the at least one of the current locationor the current date. Adjusting an output of the at least one lightsource if both the detected level of light in the ambient environment atleast satisfies the first threshold and the result of the comparison isvalid with respect to the at least one expected condition may includeturning the at least one light source ON if both the detected level oflight in the ambient environment is equal or less than a turn ONthreshold and the detected level of light in the ambient environment iswithin the second threshold of the expected level of light for thecurrent time at the current location. Adjusting an output of the atleast one light source if both the detected level of light in theambient environment at least satisfies the first threshold and theresult of the comparison is valid with respect to the at least oneexpected condition may include turning the at least one light source OFFif both the detected level of light in the ambient environment is equalor greater than a turn OFF threshold and an actual time at which thedetected level of light satisfied the first threshold is within a secondthreshold of the expected time when the level of light is predicted tosatisfy the first threshold for the at least one of the current locationor the current date. Adjusting an output of the at least one lightsource if both the detected level of light in the ambient environment atleast satisfies the first threshold and the result of the comparison isvalid with respect to the at least one expected condition may includeturning the at least one light source OFF if both the detected level oflight in the ambient environment is equal or greater than a turn OFFthreshold and the detected level of light in the ambient environment iswithin the second threshold of the expected level of light for thecurrent time at the current location. The method may further includereducing the output of the at least one light source to a non-zero levelwhen a first real time in a daily cycle is reached. The method mayfurther include detecting motion at least proximate an area beingilluminated; and in response to the detecting motion, temporallyincreasing the output of the at least one light source. The method mayfurther include increasing the output of the at least one light sourcewhen a second real time in the daily cycle is reached. When the resultof the comparison is invalid with respect to the at least one expectedcondition, the method may further include repeating at least thereducing and the increasing the output of the at least one light sourcewhen the first and the second real times, respectively, are reached fora number of additional daily cycles. Repeating at least the reducing andthe increasing of the output of the at least one light source when thefirst and the second real times, respectively, are reached for a numberof additional daily cycles, may further include turning ON the at leastone light source at a time in a daily cycle that corresponds to dusk andturning OFF the at least one light source at a time in the daily cyclethat corresponds to dawn. The method may further include producing bythe controller an external notification if the detected level of lightin the ambient environment is not within the second threshold of theexpected level of light for the current time at the current location.The method may further include in response to determining that theresult of the comparison is invalid, causing the output of the at leastone light source to be at least proximate a highest level of the atleast one light source.

A system to control illumination may be summarized as including at leastone controller that: from time-to-time, receives a signal indicative ofa level of light in an ambient environment; compares the detected levelof light in the ambient environment to an expected level of light for atleast one of a current time or a current location; compares the detectedlevel of light in the ambient environment to a first threshold;validates a result of the comparison of the detected level of light inthe ambient environment to the first threshold with respect to at leastone expected condition; and adjusts an output of the at least one lightsource if both the detected level of light in the ambient environment atleast satisfies the first threshold and the result of the comparison isvalid with respect to the at least one expected condition.

To validate a result of the comparison of the detected level of light inthe ambient environment to the first threshold with respect to at leastone expected condition, the at least one controller may: compare anactual time at which the detected level of light satisfied the firstthreshold to an expected time when the level of light is predicted tosatisfy the first threshold for at least one of a current location or acurrent date; determine that the result of the comparison is valid ifthe actual time at which the detected level of light satisfied the firstthreshold is within a second threshold of the expected time when thelevel of light is predicted to satisfy the first threshold for the atleast one of the current location or the current date; or determine thatthe result of the comparison is invalid if the actual time at which thedetected level of light satisfied the first threshold is not within thesecond threshold of the expected time when the level of light ispredicted to satisfy the first threshold for the at least one of thecurrent location or the current date. To validate a result of thecomparison of the detected level of light in the ambient environment tothe first threshold with respect to at least one expected condition, theat least one controller may: compare the detected level of light in theambient environment to an expected level of light for at least one of acurrent location, a current date or a current time; determine that theresult of the comparison is valid if the detected level of light in theambient environment is within a second threshold of the expected levelof light for the at least one of the current location, the current dateor the current time; or determine that the result of the comparison isinvalid if the detected level of light in the ambient environment is notwithin the second threshold of the expected level of light for the atleast one of the current location, the current date or the current time.The at least one controller may compare the detected level of light to avalue indicative of an expected level of light for the current time atthe current location. The system may further include an ambient lightsensor, wherein the at least one controller continuously receives asignal from the ambient light sensor, the signal indicative of the levelof light in the ambient environment. The at least one controller mayfurther receive a location signal indicative of the current location;and may determine at least one of an excepted level of light or anexpected time at which the level of light is predicted to satisfy thefirst threshold based at least in part on the current locationidentified by the location signal. The at least one controller mayfurther receive a time signal indicative of the current time. The systemmay further include an antenna; and a global positioning receivercommunicatively coupled to the antenna to receive a global positioningsignal from a number of global positioning system satellites, whereinthe at least one controller is communicatively coupled to the globalpositioning receiver to receive the location signal indicative of thecurrent location. The system may further include an antenna; and acellular communications receiver communicatively coupled to the antennato receive a cellular communications signal from a number of cellularcommunications antennas, wherein the at least one controller iscommunicatively coupled to the cellular communications receiver toreceive the location signal indicative of the current location. Toadjust the output of the at least one light source if both the detectedlevel of light in the ambient environment at least satisfies the firstthreshold and the result of the comparison is valid with respect to theat least one expected condition the at least one controller may turn theat least one light source ON if both the detected level of light in theambient environment is equal or less than a turn ON threshold and anactual time at which the detected level of light satisfied the firstthreshold is within a second threshold of the expected time when thelevel of light is predicted to satisfy the first threshold for the atleast one of the current location or the current date. To adjust theoutput of the at least one light source if both the detected level oflight in the ambient environment at least satisfies the first thresholdand the result of the comparison is valid with respect to the at leastone expected condition the at least one controller may turn the at leastone light source ON if both the detected level of light in the ambientenvironment is equal or less than a turn ON threshold and the detectedlevel of light in the ambient environment is within the second thresholdof the expected level of light for the current time at the currentlocation. To adjust the output of the at least one light source if boththe detected level of light in the ambient environment at leastsatisfies the first threshold and the result of the comparison is validwith respect to the at least one expected condition the at least onecontroller may turn the at least one light source OFF if both thedetected level of light in the ambient environment is equal or greaterthan a turn OFF threshold and an actual time at which the detected levelof light satisfied the first threshold is within a second threshold ofthe expected time when the level of light is predicted to satisfy thefirst threshold for the at least one of the current location or thecurrent date. To adjust the output of the at least one light source ifboth the detected level of light in the ambient environment at leastsatisfies the first threshold and the result of the comparison is validwith respect to the at least one expected condition the at least onecontroller may turn the at least one light source OFF if both thedetected level of light in the ambient environment is equal or greaterthan a turn OFF threshold and the detected level of light in the ambientenvironment is within the second threshold of the expected level oflight for the current time at the current location. The at least onecontroller may reduce the output of the at least one light source to anon-zero level when a first real time in a daily cycle is reached. Theat least one controller may further detect motion at least proximate anarea being illuminated; and in response to the detection of motion,temporally increase the output of the at least one light source. The atleast one controller may further increase the output of the at least onelight source when a second real time in the daily cycle is reached. Whenthe result of the comparison is invalid with respect to the at least oneexpected condition, the at least one controller may further repeat atleast the reducing and the increasing the output of the at least onelight source when the first and the second real times, respectively, arereached for a number of additional daily cycles. Repeating at least thereducing and the increasing of the output of the at least one lightsource when the first and the second real times, respectively, arereached for a number of additional daily cycles may further includeturning ON the at least one light source at a time in a daily cycle thatcorresponds to dusk and turning OFF the at least one light source at atime in the daily cycle that corresponds to dawn. The at least onecontroller may further produce an external notification if the detectedlevel of light in the ambient environment is not within the secondthreshold of the expected level of light for the current time at thecurrent location. When the result of the comparison is invalid withrespect to the at least one expected condition the at least onecontroller may cause the output of the at least one light source to beat least proximate a highest level of the at least one light source. Thesystem may further include the at least one light source.

A method of operating an illumination system including at least onelight source may be summarized as including determining by a controller,an expected ambient environment illumination condition for a currentlocation at a defined date and time; comparing by the controller, anactual ambient environment illumination condition detected in theambient environment at the current location with the determined expectedambient environment illumination condition; and in response todetermining an existence of a difference between the actual ambientenvironment illumination condition and the determined expected ambientenvironment illumination condition, producing by the controller, atleast one of a notification or a record indicative of an aberrant event.

The method may further include receiving a location signal by thecontroller, the location signal indicative of a current location of theillumination system. Determining by a controller an expected ambientenvironment illumination condition may include determining at least oneof an expected time of dusk or an expected time of dawn for the currentlocation based at least in part on the current location indicated by thelocation signal. Determining by a controller, an expected ambientenvironment illumination condition may include determining an expectedlevel of illumination in the ambient environment for the currentlocation at a defined time based at least in part on the currentlocation indicated by the location signal. Receiving a location signalby the controller may include receiving a location signal from a globalpositioning system receiver. Receiving a location signal by thecontroller may include receiving a location signal from a cellularcommunications system receiver. The method may further include detectinga level of light in an ambient environment via an ambient light sensor.Producing a notification may include transmitting a signal externallyfrom the illumination system. Producing a notification may includeilluminating a warning indicator of the illumination system. Comparingan actual ambient environment illumination condition with the determinedexpected ambient environment illumination condition may include at leastone of: determining whether a detected level of illumination in theambient environment is below an expected level of illumination by morethan the defined threshold or determining whether the detected level ofillumination in the ambient environment is above the expected level ofillumination by more than the defined threshold. Comparing an actualambient environment illumination condition with the determined expectedambient environment illumination condition may include at least one of:determining whether an actual time when dusk in the ambient environmentis detected is within a first threshold of an expected time at whichdusk was predicted or whether an actual time when dawn in the ambientenvironment is detected is within a second threshold of an expected timeat which dawn was predicted.

A system to control illumination may be summarized as including at leastone controller that: determines an expected ambient environmentillumination condition for a current location at a defined date andtime; compares an actual ambient environment illumination conditiondetected in the ambient environment a the current location with thedetermined expected ambient environment illumination condition; and inresponse to a determination that a difference between the actual ambientenvironmental illumination condition and the determined expected ambientenvironment illumination condition, produces at least one of anotification or a record indicative of an aberrant event.

The at least one controller may receive a location signal, the locationsignal indicative of a current location of the illumination system. Todetermine an expected ambient environment illumination condition the atleast one controller may determine at least one of an expected time ofdusk or an expected time of dawn for the current location based at leastin part on the current location indicated by the location signal. The atleast one controller may determine an expected level of illumination inthe ambient environment based at least in part on the current locationindicated by the location signal. The system may further include anantenna; and a global positioning receiver communicatively coupled tothe antenna to receive a global positioning signal from a number ofglobal positioning system satellites, wherein the at least onecontroller is communicatively coupled to the global positioning receiverto receive the location signal indicative of the current location. Thesystem may further include an antenna; and a cellular communicationsreceiver communicatively coupled to the antenna to receive a cellularcommunications signal from a number of cellular communications antennas,wherein the at least one controller is communicatively coupled to thecellular communications receiver to receive the location signalindicative of the current location. The system may further include anambient light sensor communicatively coupled to provide ambient lightlevel signals to the at least one controller. The at least onecontroller may produce the notification as a signal transmit externallyfrom the system. The at least one controller may produce thenotification as an illuminated warning indicator of the system. Tocompare an actual ambient environment illumination condition with thedetermined expected ambient environment illumination condition the atleast one controller may determine at least one of whether a detectedlevel of illumination in the ambient environment is below an expectedlevel of illumination by more than the defined threshold or whether thedetected level of illumination in the ambient environment is above theexpected level of illumination by more than the defined threshold. Tocompare an actual ambient environment illumination condition with thedetermined expected ambient environment illumination condition the atleast one controller may determine whether an actual time when dusk inthe ambient environment is detected is within a first threshold of anexpected time at which dusk was predicted or whether an actual time whendawn in the ambient environment is detected is within a second thresholdof an expected time at which dawn was predicted. The system may furtherinclude at least one light source; and wherein the at least onecontroller adjusts a level of illumination produced by the at least onelight source.

A method of operating an illumination system including at least onelight source may be summarized as including receiving a signal by acontroller from an external source, the signal indicative of at leastone of a current location of the illumination system, a current date ora current time; and controlling a level of illumination produced by theat least one light source based at least in part on at least one of thecurrent location of the illumination system, the current date or thecurrent time.

Receiving a signal by the controller may include receiving a signal viaa global positioning system receiver from at least one globalpositioning satellite. The method may further include determining by acontroller, an expected level of illumination in an ambient environmentbased at least in part on at least one of the current location of theillumination system, the current date or the current time; comparing bythe controller, a detected level of illumination in the ambientenvironment with the determined expected level of illumination in theambient environment; and in response to determining an existence of adifference between the detected level of illumination in the ambientenvironment and the determined expected level of illumination in theambient environment which exceeds a defined threshold, producing by thecontroller, at least one of a notification or a record indicative of theexistence. The method may further include determining by a controller,an expected time of at least one of dusk or dawn based at least in parton at least one of the current location of the illumination system, thecurrent date or the current time; comparing by the controller, adetected occurrence of at least one of dusk or dawn in the ambientenvironment with the determined expected time of at least one of dusk ordawn; and in response to determining an existence of a differencebetween the detected occurrence of at least one of dusk or dawn and thedetermined expected time of at least one of dusk or dawn which exceeds adefined threshold, producing by the controller, at least one of anotification or a record indicative of an aberrant condition.

A system to control illumination may be summarized as including at leastone antenna; at least one receiver communicatively coupled to the atleast one antenna to receive signals from an external source, thesignals indicative of at least one of a current location of theillumination system, a current date or a current time; and at least onecontroller communicatively coupled to the at least one receiver toreceive information therefrom, and which controls a level ofillumination produced by the at least one light source based at least inpart on at least one of the current location of the illumination system,the current date or the current time.

The at least one receiver may be a global positioning receivercommunicatively coupled to the antenna to receive a number of globalpositioning signals from a number of global positioning systemsatellites. The at least one controller may: determine an expected levelof illumination in the ambient environment based at least in part on thecurrent location, the current date or the current time; compare adetected level of illumination in the ambient environment with thedetermined expected level of illumination in the ambient environment;and in response to determining an existence of a difference between thedetected level of illumination in the ambient environment and thedetermined expected level of illumination in the ambient environmentwhich exceeds a defined threshold, produce at least one of anotification or a record indicative of an aberrant condition. The atleast one controller may: determine an expected time of at least one ofdusk or dawn based at least in part on at least one of the currentlocation of the illumination system, the current date or the currenttime; compare a detected occurrence of at least one of dusk or dawn inthe ambient environment with the determined expected time of at leastone of dusk or dawn; and in response to a determination that anexistence of a difference between the detected occurrence of at leastone of dusk or dawn and the determined expected time of at least one ofdusk or dawn which exceeds a defined threshold, produce at least one ofa notification or a record indicative of an aberrant condition.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

In the drawings, identical reference numbers identify similar elementsor acts. The sizes and relative positions of elements in the drawingsare not necessarily drawn to scale. For example, the shapes of variouselements and angles are not drawn to scale, and some of these elementsare arbitrarily enlarged and positioned to improve drawing legibility.Further, the particular shapes of the elements as drawn, are notintended to convey any information regarding the actual shape of theparticular elements, and have been solely selected for ease ofrecognition in the drawings.

FIG. 1 is a partially exploded isometric diagram showing a conventionalluminaire, light source and a retrofit control subsystem selectivelyattachable in place of the legacy dusk to dawn sensor, according to onenon-limiting illustrated embodiment.

FIG. 2 is a partially exploded isometric diagram showing a conventionalluminaire, conventional light sources and a retrofit control subsystemselectively attachable between the luminaire and light source, accordingto another non-limiting illustrated embodiment.

FIG. 3 is a schematic diagram showing a conventional luminaire withoptical sensor(s) and a dusk-to-dawn control mechanism, a light sourceand a retrofit control subsystem, according to one non-limitingillustrated embodiment.

FIG. 4A is an isometric diagram showing a luminaire including anintegral control subsystem and a light source, according to anothernon-limiting illustrated embodiment.

FIG. 4B is right side elevational view of the luminaire of FIG. 4A.

FIG. 5 is a schematic diagram showing the luminaire of FIGS. 4A and 4Bwith the integral control subsystem, and a light source.

FIG. 6A is a graph showing a level of illumination or output versus timeover two daily cycles during a first part of a year, according toanother non-limiting illustrated embodiment.

FIG. 6B is a graph showing a level of illumination or output versus timeover two daily cycles during a second part of a year where there is lessdaylight in a daily cycle.

FIG. 6C is a graph showing a level of illumination or output versus timeover two daily cycles during the first part of a year, according toanother non-limiting illustrated embodiment where a dusk sensingthreshold is set to be reached earlier while a dawn sensing threshold isset to be reached later in the daily cycle.

FIG. 6D is a graph showing a level of illumination or output versus timeover two daily cycles during the first part of a year, according toanother non-limiting illustrated embodiment the dusk and dawn sensingthresholds are set such as to produce uneven durations of high intensityillumination.

FIGS. 7A-7C are a flow diagram showing a high level method of operatingan illumination system to provide illumination in an energy efficientmanner, according to one non-limiting illustrated embodiment.

FIG. 8 is a flow diagram showing a low level method of operating acontrol subsystem of an illumination system to validate a detection,according to one non-limiting illustrated embodiment.

FIG. 9 is a flow diagram showing a low level method of operating acontrol subsystem to validate a detection, according to anothernon-limiting illustrated embodiment.

FIG. 10 is a flow diagram showing a low level method of operating acontrol subsystem of an illumination system to determine a location ofthe illumination system based on global positioning system signals, andto determine an expected level of light based at least in part on thedetermined location, according to one non-limiting illustratedembodiment.

FIG. 11 is a flow diagram showing a low level method of operating acontrol subsystem of an illumination system to determine a location ofthe illumination system based on cellular system signals, and todetermine an expected level of light based at least in part on thedetermined location, according to another non-limiting illustratedembodiment.

FIG. 12 is a flow diagram showing a low level method of operating acontrol subsystem of an illumination system to produce a securitynotification, according to one non-limiting illustrated embodiment.

FIG. 13 is a flow diagram showing a high level method of operating acontrol subsystem of an illumination system, according to anothernon-limiting illustrated embodiment.

DETAILED DESCRIPTION

In the following description, certain specific details are set forth inorder to provide a thorough understanding of various disclosedembodiments. However, one skilled in the relevant art will recognizethat embodiments may be practiced without one or more of these specificdetails, or with other methods, components, materials, etc. In otherinstances, well-known structures associated with luminaires and imagingdevices have not been shown or described in detail to avoidunnecessarily obscuring descriptions of the embodiments.

Unless the context requires otherwise, throughout the specification andclaims which follow, the word “comprise” and variations thereof, suchas, “comprises” and “comprising” are to be construed in an open,inclusive sense that is as “including, but not limited to.”

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure or characteristicdescribed in connection with the embodiment is included in at least oneembodiment. Thus, the appearances of the phrases “in one embodiment” or“in an embodiment” in various places throughout this specification arenot necessarily all referring to the same embodiment. Furthermore, theparticular features, structures, or characteristics may be combined inany suitable manner in one or more embodiments. Additionally, the termslighting and illumination are used herein interchangeably. For instance,the phrases “level of illumination” or “level of light output” have thesame meanings. Also instance, the phrases “illumination source” and“light source” have the same meanings.

The headings and Abstract of the Disclosure provided herein are forconvenience only and do not interpret the scope or meaning of theembodiments.

FIG. 1 shows an illumination system 100 according to one non-limitingillustrated embodiment. The illumination system 100 includes aconventional luminaire 102, at least one illumination or light source104, and a retrofit control subsystem 106.

The luminaire 102 may take any of a variety of forms. For example, theluminaire 102 may include a housing 108, a shade 110 and optionally abracket 112 to allow the luminaire 102 to be hung from a structure. Theshade 110 may be transparent or translucent or may be opaque. Theluminaire 102 may include a socket, for instance a threaded socket orreceptacle 114, sized to removably or interchangeably receive a base 115of the light source 104 and wiring (not shown in FIG. 1) to providepower to the light source 104 from an external source of electricalpower, such as AC mains. As previously noted, such luminaires 102 areconventional and commercially available from a large variety of sources.

The luminaire 102 may also include a socket 116 or other coupler toallow removable physical and electrical mounting of a dusk-to-dawnsensor. Standard NEMA compliant luminaries typically include such asensor accommodating socket 116, to allow dusk-to-dawn sensors to beeasily replaced. The socket 116 may be positioned to allow thedusk-to-dawn sensor to be favorably positioned to have an unimpededfield-of-view. For example, the socket 116 may be positioned on top ofthe housing 108 such that a sensor mounted thereto generally facesskyward. While illustrated as threaded, other types of sockets,receptacles or couplers may be employed.

The luminaire 102 may include a luminaire control circuit 120.Typically, the luminaire control circuit 120 is configured to turn thelight source 104 ON when a level of light detected by a sensor mountedvia the socket 116 is below a turn ON threshold and to turn the lightsource 104 OFF when the level of light detected by the sensor is above aturn OFF threshold. The turn ON and turn OFF thresholds may, or may not,be equal to one another.

The light source 104 may take a variety of forms. The light source mayinclude one or more distinct light bulbs, lights or light emitters 122a-122 n (only two called out in FIG. 1). For example, the light source104 may take the form of one or more incandescent light bulbs. Also forexample, the light source 104 may take the form of one or moreflorescent light bulbs such as HID light bulbs or lights, one or morearc lamps, or one or more gas-discharge lamps. Advantageously, the lightsource 104 may take the form of one or more solid state light sources,for instance an array of LEDs, OLEDs or PLEDs. While illustrated as abulb, the light sources do not necessarily have to be enclosed in a bulbstructure. For example, the light sources may take the form of one-,two-, or even three-dimensional arrays of individual LEDs or strings ofLEDs. Where appropriate, the light source 104 may also include a ballast124, for example an electronic ballast.

The retrofit control subsystem 106 is selectively attachable, mountableor coupleable to the luminaire 102 and luminaire control circuit 102,and hence to the light source 104. In particular, the retrofit controlsubsystem 106 includes a base 126 sized to be received in the sensorreceiving socket or receptacle 116 of the luminaire 102. Typically, thebase 126 will have a three contact plug which allows the base 126 to beremovably or detachably received by the socket or receptacle 116 of theluminaire 102. The socket 114 and base 126 provide both physicalcoupling between the luminaire 102 and the retrofit control system 106and electrical coupling between the luminaire control circuit 120 andthe retrofit control system 106.

The retrofit control subsystem 106 includes at least one sensor 118(e.g., photosensor, cadmium sulfide cell, photodiode, phototransistor,ambient light sensor integrated circuit) that is responsive to a level(e.g., energy or intensity) of light or illumination in the environment(e.g., daylight or ambient light). The sensor 118 may be positioned tominimize an effect of the light source 104 on the sensor 118. Forexample, the sensor 118 may be positioned on be on top of the housing108 when the retrofit control subsystem 106 is mounted via the sensorreceiving socket 118.

The retrofit control subsystem 106 also includes electrical circuitry,electronics, software and/or firmware that adjusts an illumination leveldownward at a time after the light source is turned ON and adjusts theillumination level upward at a time preceding the light source beingturned OFF. Such provides lighting at relatively high levels whenillumination is typically most useful, while providing lighting atreduced levels when illumination is not typically useful, therebyreducing energy usage. The electrical circuitry, electronics, softwareand/or firmware may also verify that detected levels of light are withinsome defined threshold(s) of expected levels of light for a givenlocation, date and/or time. Alternatively, the electrical circuitry,electronics, software and/or firmware may also verify that a time atwhich an event or condition (e.g., dusk, dawn) is detected is withinsome defined threshold(s) of expected time at which the event orcondition was predicted to occur for a given location, date and/or time.Such validation of levels or time may allow detection of aberrationssuch as unintentional component failures or interference or evenintentional tampering or interference with the luminaire, and automaticnotification or alerts regarding the detection of such aberrations. Suchmay also allow operation to continued, even if an aberrant conditionoccurs. The electrical circuitry, electronics, software and/or firmwaremay automatically determine a current location of the luminaire, currentdate and/or current time, based at least in part on signals receivedfrom an external source (e.g., global positioning satellites, cellularcommunications base stations, WiFi sources). Such may advantageouslyreduce, or even eliminate, the need for training or adaptive learningover multiple daily cycles, and produce more accurate responses thancould be produced using training or adaptive learning based approaches.

Such is possible via a retrofit to existing luminaires. Such may avoidthe drawbacks associated with motion or proximity based control, such asthe limited range of motion or proximity sensors and lack of sensitivityof such sensors in warm climates. As described in more detail below, theretrofit control subsystem 106 may monitor the local time of day andlocation from received data, and advantageously employ such incontrolling the light source 104. Such can automatically accommodateseasonal changes in the length of daylight or night.

FIG. 2 shows an illumination system 200 according to anothernon-limiting illustrated embodiment. The illumination system 200includes a conventional luminaire 202, illumination or light sources 204a, 204 b, and retrofit control subsystems 206 a, 206 b (only one visiblein FIG. 2).

The luminaire 202 may take any of a variety of forms. For example, theluminaire 202 may include a housing 208, two shades 210 a, 210 b, and atleast one optical sensor 218. The housing 208 allows the luminaire 202to be hung from a structure. The shades 210 a, 210 b each include arespective socket or receptacle 214 a, 214 b sized to receive a base 215a (only one visible in FIG. 2) of the light source 204 a, 204 b. Theshades 210 a, 210 b may be supported from the housing 208 by respectivearticulated arms 230 a, 230 b. The arms 230 a, 230 b may include one ormore joints 232 a, 232 b to provide multiple degrees of freedom whichallows the shades 210 a, 210 b and respective light sources 204 a, 204 bto be positioned and oriented in any desired manner. The optical sensor218 may be supported from the housing 208 by an arm 234, for example viaa ball joint 236. Such may allow the optical sensor 218 to be positionedand oriented with respect to the housing 208 and any structure to whichthe housing is mounted. As previously noted, such luminaires 202 areconventional and commercially available from a large variety of sources.

Luminaires 202 of this type typically have a control mechanism thatimplements both dusk-to-dawn and motion or proximity based control.Thus, the control mechanism relies on signals from the optical sensor toimplement motion or proximity sensing only during a period after a levelof light or illumination in the environment has fallen below a turn ONthreshold (e.g., 10 Lux) and before the level of illuminations exceeds aturn OFF threshold (e.g., 30 Lux). The control mechanism will turn thelight sources 204 a, 204 b ON for a period of time in response to thedetection of motion between dusk and dawn, turning the light sources 204a, 204 b OFF after the period of time.

Respective retrofit control subsystems 206 a, 206 b are selectivelyattachable or coupleable between the sockets or receptacles 214 a, 214 bof the luminaire 202 and the bases 215 a of the light sources 204 a, 204b to provide an interface therebetween. In particular, the retrofitcontrol subsystems 206 a, 206 b include a base 226 a (only one visiblein FIG. 2) sized to be received in the sockets or receptacles 214 a, 214b of the luminaire 202. Typically, the base 226 a will have a threadwhich allows the base 226 a to be threadedly removably or detachablyreceived by the socket or receptacle 214 a, 241 b of the luminaire 202.The socket 214 a, 214 b and base 214 a provide both physical andelectrical coupling between the luminaire 202 and the respectiveretrofit control system 206 a, 206 b. The retrofit control subsystems206 a, 206 b also include a socket or receptacle 228 a (only one visiblein FIG. 2) sized to receive the base 215 a of the light source 204 a,204 b. Typically, the socket or receptacle 228 a has a thread whichallows the base 215 a of the light source 204 to be threadedly removablyor detachably received by the socket or receptacle 228 a. The socket 228a and base 215 a provide both physical and electrical coupling betweenthe retrofit control subsystem 206 a, 206 b and the respective lightsource 204 a, 204 b.

As discussed above, the retrofit control subsystems 206 a, 206 b includeelectrical circuitry, electronics, software and/or firmware that adjustan illumination level downward (i.e., decrease) at a time after thelight source is turned ON and adjust the illumination level upward(i.e., increase) at a time preceding the light source being turned OFF.Such provides lighting at relatively high levels when illumination istypically most useful, while providing lighting at reduced levels whenillumination is not typically useful, thereby reducing energy usage. Theelectrical circuitry, electronics, software and/or firmware may alsoverify that detected levels of light are within some definedthreshold(s) of expected levels of light for a given location, dateand/or time. Such may allow detection of aberrations such asunintentional component failures or unintentional interference with, oreven intentional tampering or interference with, the luminaire, andautomatic notification or alerts regarding the detection of suchaberrations. Such may also allow operation to continued, even if anaberrant condition occurs. The electrical circuitry, electronics,software and/or firmware may automatically determine a current locationof the luminaire, current date and/or current time, based at least inpart on signals received from an external source (e.g., globalpositioning satellites, cellular communications base stations, WiFisources). Such may advantageously reduce, or even eliminate, the needfor training or adaptive learning over multiple daily cycles, andproduce more accurate responses than could be produced using training oradaptive learning based approaches.

Such is possible via a retrofit to existing luminaires. Such may avoidthe drawbacks associated with motion or proximity based control, such asthe limited range of motion or proximity sensors and lack of sensitivityof such sensors in warm climates. As described in more detail below, theretrofit control subsystem 206 a, 206 b may monitor the local time ofday and location from received data, and advantageously employ such incontrolling the light source 204 a, 204 b. Such can automaticallyaccommodate seasonal changes in the length of daylight or night.

FIG. 3 schematically illustrates an illumination system 300, accordingto one non-limiting illustrated embodiment.

The illumination system 300 may employ a conventional luminaire 302, forexample identical or similar to those illustrated in FIGS. 1 and 2. Theluminaire 302 may include an optical sensor 304 and a control mechanism306. The optical sensor 304 can take any variety of forms, includinglight sensitive or light responsive photosensors, cadmium sulfide cells,photodiodes, phototransistors, ambient light sensor integrated circuitscurrently commercially available. The control mechanism 306 may be ananalog circuit, digital circuit or may include both analog and digitalcircuit components, as well as software or firmware instructionsexecutable by one or more processors, for instance microprocessors,digital signal processors, programmable gate arrays or applicationspecific integrated circuits. Again, a conventional commerciallyavailable luminaire with an integral control mechanism may be employed.

The illumination system 300 may include at least one illumination orlight source 308, for example identical or similar to those discussedwith reference to FIG. 1. In particular, the illumination system 300 mayemploy a light source 308 that includes an array of solid-state lightsources or emitters, such as LEDs, OLEDs or PLEDs. The illuminationsystem 300 may include a ballast 310 for the light source 308. Theballast 310 may be an integral or unitary part of the light source 308,or may be a separate discrete component therefrom.

As previously explained, the control mechanism 306 may take the form ofa dusk-to-dawn photo control mechanism configured to turn the lightsource(s) 308 ON when the sensor 304 senses a level of illumination orlight in the environment that is at or below a turn ON threshold. Thecontrol mechanism 306 may be configured to turn the light source(s) 308OFF when the sensor 304 senses a level of light in the environment thatis at or above a turn OFF threshold. While the turn ON and turn OFFthresholds could be equivalent, such would likely produce undesirableoscillation. Hence, some separation should be maintained between theturn ON and turn OFF thresholds. For example, the turn ON threshold mayequal 10 LUX while the turn OFF threshold may equal 30 LUX.

The illumination system 300 may include one more retrofit controlsubsystems 312. The retrofit control subsystem 312 may be identical orsimilar to the retrofit control subsystem 106, 206 (FIGS. 1 and 2). Theretrofit control subsystem 312 may, for example, include amicrocontroller 314 and one or more non-volatile storage media 316communicatively coupled to the microcontroller 314. The microcontroller314 may take any of a variety of forms, for example a microprocessor,programmable gate array (PGA), application specific integrated circuit(ASIC), etc. The non-volatile storage media 316 may take any of avariety of forms, for example electrically erasable programmable readonly memories (EEPROMs), flash memories, etc.

The retrofit control subsystem 312 may additionally include one or moreantennas (only one illustrated) 317 and one or more receivers 318 (onlyone illustrated) communicatively coupled to at least one of the antennas317 and to the microcontroller 314. The antenna 317 may be internal tothe retrofit control subsystem 312 or may be electrically coupled to theretrofit control subsystem 312 such that the antenna may be extended toan outer side of the shade 110, 210 a, 210 b (FIGS. 1 and 2). Thereceiver 318 may also be positioned within the retrofit controlsubsystem 312. The receivers 318 may take a variety of forms for examplea global positioning system (GPS) receiver, a cellular communicationssystem receiver, a wireless telecommunications receiver (e.g., WiFi), alandline transceiver, or a radio (e.g., AM, FM, Satellite) receiver. Thereceiver 318 may provide information to the retrofit control subsystem312, such as information which is indicative of a current location ofthe illumination system, and/or information that is indicative of acurrent date, and/or time of day. As will be discussed in more detailbelow, the retrofit control subsystem 312 may use information from thereceiver 318 to determine an expected level of light in the ambientenvironment, for example, to calibrate the dusk-to-dawn controller 306and/or to implement security features to the illumination system 300.

The retrofit control subsystem 312 is electrically coupled to thecontrol mechanism 306 of the luminaire 302, for example via a socket andbase. The components of the retrofit control subsystem 312 may receivepower via this coupling or a standalone power source may be included.The retrofit control subsystem 312 may include power supply circuitry313 that rectifies, steps down a voltage and otherwise transforms orconditions supplied electrical power to a form suitable to power themicrocontroller 314, non-volatile storage media 316 and/or othercomponents of the retrofit control subsystem 312.

While the retrofit control subsystem 312 is illustrated as being coupledbetween the luminaire 302 and light source 308, some embodiments mayemploy one or more relays (not illustrated) to provide electrical powerto the light source 308 from the luminaire 302. The retrofit controlsubsystem 312 may employ a conventional light dimmer circuit to controllight level output by the light source 308. Alternatively oradditionally, a network link to a programmable lamp controller may beemployed. Alternatively or additionally, an analog voltage applied to adimmable lamp controller may be employed, or a resistor switched into adimming input of a dimmable lamp controller. Alternatively oradditionally, the retrofit control subsystem may use one or moreswitches (e.g., contact switches, relays, transistors, triacs) to switchin or out individual or groups of light emitters that make up one ormore light sources, or lamp controllers which control the light sources.

The retrofit control subsystem 312 receives signals from the controlmechanism 306 of the luminaire 302 which are indicative of when thecontrol mechanism 306 attempts to turn the light source 308 ON and OFFin response to a sensed illumination level being below a turn Onthreshold and below a turn OFF threshold, respectively. The signals maybe as simple as providing electrical power to power the light source 308then not providing electrical power. The lamp may be turned on to fullbrightness or almost full brightness in response to the dusk-to-dawnsensor sensing an illumination level falling below a defined threshold(e.g., dusk threshold), then using the data received from a wirelesssource to adjust the illumination level down at a pre-programmed time ofday, then adjust the illumination level back to full illumination atanother preprogrammed time of day, and finally turned OFF when the duskto dawn sensor signals an illumination level above a threshold (e.g.,dawn threshold).

The microcontroller 314 can determine an expected level of light for theambient environment based upon information received by the receiver 318.For instance, the receiver 318 may provide GPS data such as longitudeand/or latitude data indicative of the current location of theillumination system 300 and optionally the current time of day. Further,the receiver may provide weather or other information which may beindicative of certain aspects (e.g., expected level of illumination) ofthe ambient environment for a give time and geographic location. Fromthe location and time of day, the microcontroller 314 may determinetimes at which to turn lighting ON, turn lighting OFF, increase a levelof illumination and/or decrease a level of illumination. Themicrocontroller 314 may additionally, or alternatively, determined anexpected level of light in the ambient environment for a given time ofday, based at least in part on the location. The microcontroller 314may, for example, access data stored within the non-volatile storage316, such as sunrise/sunset tables, almanac information, and/or daylightsavings time tables, to determine and compare an expected level of lightfor a given time of day with a detected level of light. Differencesbetween the detected level of light and the expected level of light maybe used to trigger an event, such as increase the level of light fromthe illumination system 300, an aural notification (e.g., an alarm),and/or a transmission of a data notification (e.g., through a wirelesshome network, cellular network, telephone line, or a security system).

In some embodiments, the retrofit control subsystem 312 may include areal time or solar clock 320 (i.e., a clock that tracks time in the realworld or with respect to the sun, rather than an internal clock of aprocessor based system). Alternatively, the microcontroller 314 mayimplement a real time or solar clock. The real time or solar clocks maybe automatically calibrated by the microcontroller 314 based uponinformation received from the receiver 318. Such embodiments may alsoinclude a discrete internal power source 322 (e.g., battery cells,capacitors, super- or ultracapacitors, fuel cell) to supply power to theclock 320 while power is not being received from the control mechanism302 of the luminaire. The internal power source 322 may be rechargeable,via the power supply circuitry 313. The microcontroller 314 maydetermine solar midnight, from time-to-time (e.g., each daily cycle). Inparticular, the microcontroller may divide the average or median timethat the light source is ON in half, which should occur at the darkesttime of the daily cycle (e.g., solar midnight). The microcontroller 314may calibrate the real time clock with the determined solar midnight.The microcontroller 314 may control the increasing and decreasing of thelevel of light output by the light source 308 using the calibrated realtime clock 320. This can prevent or reduce the effect of artificiallights on the illumination system 300.

The operation is further described with reference to the methodsillustrated in FIGS. 7-18, below.

FIGS. 4A and 4B show an illumination system 400 according to onenon-limiting illustrated embodiment. The illumination system 400includes a luminaire 402 and at least one light source 404. Theillumination system 400 may also include a sensor 418 that is responsiveto a level of light or illumination in the ambient environment, areceiver 420 (e.g., GPS receiver, cellular receiver), and a motiondetector 422. The illumination system 400 may further include anintegral control subsystem 406 and an antenna 424.

The luminaire 402 may take a variety of forms. Such forms includeluminaires that hold one, two, or more light sources 404. The luminaire402 may also include a reflector 407, a housing 408, a shade 410. Thebrackets 412 may be used with attachment clips to attach a retrofitluminaire (all parts except 408) to an existing, previously installedhousing 408. The housing 408 and shade 410 may be in the shape of acircle, oval, square, rectangle, triangle, or other polygon. The housing408 and shade 410 may share a common shape or they may be differentshapes from one another.

The light source 404 can take a variety of forms. For example, the lightsource 404 may be comprised of one or more incandescent lamps,fluorescent lamps, or any of the various types of light emitting diodes(LEDs). The light source 404 that is selected for use in the luminaire402 may be based upon the intended use of the illumination system 400.For example, a brighter illuminating source may be selected over a moreenergy efficient source based upon whether the area to be illuminated isresidential or commercial, densely populated or rural, and secured orpublic and/or on the relative cost of locating sufficient luminaries tosatisfactorily cover the area to be illuminated.

The reflector 407 may be optionally positioned around the light source404 to mitigate light trespass. For example, the reflector 407 maydefine and limit the angle of the illumination footprint so as not toilluminate a backyard or window of a neighboring home or structure. Thereflector 407 may provide the additional benefit of reducing lightpollution, which obscures the stars in the night sky, interferes withastronomical research, and may disrupt ecosystems.

The heat sink 426 may be optionally positioned around the light source404 to transfer thermal energy away from the light source 404. Trappedthermal energy in solid state devices may alter the color of the lightsource 404 or alter the operational characteristics, such as thresholdvoltages in transistors, of components within the light source 404, aswell as reduce the life of the light source 404. The heat sink 426 maybe composed of one or more thermal conductors such as aluminum andcopper or thermally filled polymers, and may include a convolutedsurface (e.g., fins, pins) to provide significantly more surface areafor a given volume occupied.

The illumination system 400 may use the sensor 418, the receiver 420,and/or the motion detector 422 to determine when to adjust the state ofthe light source 404 between ON, OFF, and to adjust illumination levelsbetween ON and OFF. In particular, the illumination system 400 may useinformation received via the receiver 420 to determine an expected levelof light in the ambient environment based at least in part on a currentlocation of the illumination system 400 as indicated in the receivedinformation, and optionally in conjunction with a current date and/orcurrent time. The illumination system 400 may use a geographical look uptable, sunrise/sunset chart, or similar form of organized data stored innon-volatile memory, or may use one or more formulas or algorithms toanalytically calculate such based in the received information. Inaddition, daylight savings time status may be determined by thecontroller based on the location data and a geographical lookup tableother method. The received information may be pre-processed by thereceiver 420, for example converting signals from two or moregeographically disparate sources into longitude and/or latitudeinformation. Alternatively, a microprocessor or other controller of theintegral control subsystem 406 may process the received information todetermine the current geographic coordinates and/or current date/time.Alternatively, data encoded in a cellular communications signal may beused to determine local time and location.

As best illustrated in FIG. 4B, the light source 404 may be removablycoupled to the luminaire 402, for instance via a threaded socket orreceptacle 405. Alternatively, the light source 404 may be integral tothe luminaire 402, particularly where the light source 404 includes aplurality of solid-state light emitters.

The integral control subsystem 406 includes circuitry to controloperation of the illumination system 400 in a similar fashion to theoperation described above. In particular, the integral control subsystem406 interfaces with at least one sensor 418 (e.g., photosensor, cadmiumsulfide cell, photodiode, phototransistor, ambient light sensorintegrated circuit) that is responsive to a level of light in theenvironment (e.g., daylight or ambient light). The sensor 418 may bepositioned to minimize an effect of the light source 404 on the sensor418. For example, the sensor 418 may be positioned on top of the housing408 or on the shade 410.

In contrast to the illumination system 200 of FIG. 2 which receivesignals from the control mechanism, in the illumination system 400 thecontrol subsystem 406 may be coupled to receive signals directly fromthe sensor 418. Thus, instead of receiving ON and OFF switching or powersignals, the control subsystem 406 may receive signals indicative of asensed level of light in the environment. Thus, in addition to thepreviously described operation, the control subsystem 406 determineswhen the sensed level of light is at or below a turn ON threshold andwhen the sensed level of light is at or above a turn OFF threshold.

The integral control subsystem 406 may also directly interface with thereceiver 420 to verify or calibrate the information received from thesensor 418. For example, the control subsystem 406 may use data from aGPS receiver (e.g., Delorme GPS2058-10 GPS receiver), such as latitude,longitude, date, and time to determine an expected level of light. Asdiscussed in detail below, the control subsystem 406 may then comparethe expected level of light to the level of light sensed by the sensor418. Such may allow detection of aberrant conditions, for exampleaberrant conditions associated with unintentional failure of a componentor associated with intentional tampering with the illumination system.The use of data received from an external source may also reduce oreliminate the need for training or learning by the control system whichmight otherwise be required to establish the solar day (e.g., solarnoon, solar midnight) at the location where the luminaire is installed.The control subsystem 406 may run in a variety of modes, e.g., security,calibrate, normal, etc., and produce an output based upon the comparisonbetween the expected level of light and the actually detected level oflight and the current operational mode in which the control subsystem406 is running.

The integral control subsystem 406 may be directly coupled to theantenna 424 to provide communications with external systems. Forexample, the antenna 424 may be a radio antenna, and the controlsubsystem 406 may include hardware and/or software to extract location,date and/or time information from the radio (e.g., radio or microwaveportions of the electromagnetic spectrum) signals, such as those sentfrom the National Institute of Standards of Technology (NIST) radiostation WWVB located in Fort Collins, Colo. The control subsystem 406may then synchronize an internal clock using the received date and time(e.g., Universal Coordinated Time or UTS) to provide continued accuracyof ON and OFF switching of the light source 404.

The integral control subsystem 406 may use the antenna 424 to receivecellular communications signals. For example, the control subsystem 406may include hardware and/or software to enable receiving informationfrom, and optionally transmitting information to, a cellular network. Asubscription with a cellular network carrier may enable the controlsubsystem 406 to acquire location, date, and time data from localcellular base stations. The control subsystem 406 may performtriangulation on signals received from geographically disparate sources,for example received from three cellular system base stations, todetermine a current location of the luminaire. The control subsystem mayextract location information from data encoded in the signal receivedfrom a single cellular base station, for example, by finding theidentity of the base station and using stored data to determinelongitude and latitude, or by direct encoding of location information inthe cellular base station signal. The control subsystem 406 may alsoextract current date and/or time information from the cellularcommunications systems signals.

The subscription with a cellular network carrier may also optionallyenable the control subsystem 406 to transmit data to the cellularnetwork. For example, the control subsystem 406 may transmit data tonotify a person or system of an event, for instance an alert indicativeof detection of an aberrant condition. The notification can take theform of a short message service (SMS), text message, email, or datapacket. A notification event may be defined by a sensed level of lightbeing detected above or below a threshold of the expected level oflight. Such an event may be triggered, for example, when a detectedlevel of light is significantly below (i.e., by more than a definedthreshold) an expected level of light, for instance where a personcovers the sensor 418. Such an event may be triggered, for example, whena detected level of light is significantly above (i.e., by more than adefined threshold) an expected level of light, for instance where aperson shines a laser or other light source at the sensor 418 in orderto deceive the illumination system 400 into shutting OFF the lightsource 404 during non-daylight hours. Thus, both the above describedaberrations may be indicative of intentional tampering. Aberrations mayalternatively be indicative of an unintentional condition, for example afailed component, for instance a failed ambient light sensor 418. Theambient light sensor 418 may fail, producing a signal indicative of asensed level of light that is either higher than the actual level oflight in the ambient environment or lower than the actual level oflight. Detection of aberrant conditions, whether unintentionally orintentionally produced, may be particularly advantageous. Such may allowthe aberration to be reported, investigated, with the failed componentbeing replaced or repaired or the tampering individual being apprehendedor scared off, or allowing heightened patrolling of a secured area inresponse.

The integral control subsystem 406 may use the antenna 424, or aseparate antenna, to provide wireless telecommunications deviceservices. For example, the control subsystem 406 may include hardwareand/or software to enable receiving information from and transmittinginformation to a personal or commercial WiFi network. By providingwireless device services, the control subsystem 406 may enable a personto set various levels and times of illumination through a graphical userinterface via a personal computer. Alternatively, the wireless deviceservice may enable the illumination system 400 to be one of severalremotely controlled illumination systems, such as may be used outside ofa warehouse, at a shipyard, impoundment lot, motor pool, othertransportation facility, energy production facility, military facilityor in proximity to some other secured area.

While several embodiments of the integral control subsystem 406 aredescribed in connection to wireless implementations, the presentdisclosure also includes landline and other wired uses. For example, thecontrol subsystem 406 may include the hardware and/or software tomanipulate a landline so as to receive and transmit data at frequenciessimilar to those used by a facsimile machine or frequencies used bydigital subscriber line (DSL) standards.

FIG. 5 schematically illustrates an illumination system 500, accordingto one non-limiting illustrated embodiment. The illumination system 500may be identical or similar to the illumination system 400 illustratedin FIGS. 4A and 4B.

The illumination system 500 may employ a conventional luminaire 502, forexample identical or similar to that illustrated in FIG. 3 or FIGS. 4Aand 4B, or of any other style. The illumination system 500 includes oneor more light sources 508 and optionally one or more ballasts 510 forthe light sources 508. Suitable examples of light sources 508 aredescribed above.

The illumination system 500 includes an integral control subsystem 512which is integral to the luminaire. The integral control subsystem 512may be identical or similar to the integral control subsystem 406 (FIG.4A or FIG. 4B). The integral control subsystem 512 may include a sensor504 that senses or is responsive to varying levels of light. The sensor504 may take a variety of forms, some of which are described above. Theintegral control subsystem 512 may include one or more antennas 517(only one show) and receivers 518 (only one show). The antenna 517 andreceiver 518 may be operable to receive and transmit a variety ofsignals, some of which are described above. The integral controlsubsystem 512 may, for example, include a microcontroller 514 and one ormore non-volatile storage media 516 communicatively coupled to themicrocontroller 514. The microcontroller 514 may take any of a varietyof forms, for example a microprocessor, programmable gate array (PGA),application specific integrated circuit (ASIC), etc. The non-volatilestorage media 516 may take any of a variety of forms, for exampleelectrically erasable programmable read only memories (EEPROMs), flashmemories, etc. The microcontroller 514 may be communicatively coupled toreceive signals directly from the sensor 504, the receiver 518, and/or aclock 519. The integral control subsystem 512 may include circuitry 513that rectifies, steps down a voltage and otherwise conditions suppliedelectrical power to a form suitable to power the microcontroller 514,non-volatile storage media 516 and/or other components of the integralcontrol subsystem 512.

The integral control subsystem 512 may employ a variety of switches orother mechanisms to turn the light source 508 ON and OFF and to adjustthe level of light output by the light source 508. For example, theintegral control subsystem 512 may employ various switches orconventional dimmer circuits, for instance those circuits and circuitcomponents discussed above in reference to the retrofit controlsubsystem 312. Like the retrofit control subsystem 312, the integralcontrol subsystem 512 may adjust the level of light by adjusting a levelof light emitted by each discrete light emitter and/or by adjusting thenumber of discrete light emitters emitting light.

The microcontroller 514 receives signals from the sensor 504 which areindicative of levels of light sensed in the ambient environment aroundor proximate the sensor 504. The microcontroller 514, or some dedicatedcircuit, compares the signals to a turn ON threshold and a turn OFFthreshold. The microcontroller 514 determines whether the sensed levelof light is at or below a turn ON threshold, indicating that lighting isrequired. In response, the microcontroller 514 may verify that thesensed level of light is within some threshold of an expected level oflight, and if so may cause the light source to be turned ON at a firstoutput level, which is typically relative high for the light source. Themicrocontroller 514 may compare a programmed time of day at which toreduce the illumination level, and if the local time of day issubstantially equal to that time, turn down (i.e., decrease) theillumination level. While the illumination is at a lower level, themicrocontroller 514 may continue to compare the local time of day with aprogrammed time of day at which the illumination level is desired to beincreased, and increase the illumination level when the said times aresubstantially equal.

The microcontroller 514 determines whether the sensed level of light isat or above a turn OFF threshold, indicating that lighting is no longerrequired. In response, the microcontroller 514 may verify that thesensed level of light is within some threshold of an expected level oflight, and if so may cause the light source to be turned OFF. Inresponse to a detection of motion, the microcontroller 514 may increasea level of light output or turn ON the light sources.

Appropriate time delays hysteresis may be added or built into thecontrol subsystem 512 before the light source 110 is turned ON or OFF.During these, sensed illumination levels remain approximately constantor the microcontroller 514 will not register a single occurrence of anON or OFF threshold being met. This suppresses short-term noise eventsand thereby avoids the microcontroller 514 from being falsely triggeredto activate the light source 110 due to short-term events such asvehicle headlights or a transient moving object.

The microcontroller 514 also determines when to adjust the level ofoutput, the adjustment occurring between turning the light source ON andOFF in a daily cycle. Such has been described above, and is described inmore detail below with reference to the various methods illustrated inthe flow diagrams.

Some embodiments of the integral control subsystem 512 may include orimplement the real time or solar clock 519, similar to that discussedwith reference to FIG. 3, above. While such embodiment may include adiscrete internal power source, such typically would not be necessarywhere the integrated control subsystem 512 receives power directly fromthe AC power mains, rather than via a dusk-to-dawn control mechanism.The microcontroller 514 may control the turning ON and OFF as well asthe increasing and decreasing of the level of light output by the lightsource using the calibrated real time clock 519. The microcontroller 514may also synchronize the real time clock based on received signalsindicative of a current date and/or current time at the particularlocation at which the illumination system 500 is installed.

The microcontroller 514 may use the receiver 518 to obtain informationin order to perform various functions. For example, the microcontroller514 may use the receiver 518 to acquire location data (e.g., GPS data,cellular base station location signal strength, etc.), to determine acurrent location. The microcontroller 514 may use the receiver 518 tointerface with a communications network, for example a cellular network,to receive radio signals including date and time, to interface with awireless telecommunications network (e.g., WiFi, WAN, LAN, MAN) and/orto interface with a wired or wireless security system. Variousadditional features that may exist in these embodiments have beendiscussed above (FIGS. 4A and 4B). For example, the microcontroller 514may use GPS data to determine an expected level of light for comparisonwith a sensed level of light. The microcontroller 514 may initiate anotification event or transmit an alert through any one of orcombination of a cellular network, a wireless telecommunicationsnetwork, or a landline interface to transmit notification of anomaliesor interferences with normal operations of the illumination system 500.According to one embodiment, the microcontroller 514 interfaces withreceiver 518 to provide wireless device services enabling a person toaccess and set various turn ON and turn OFF thresholds through agraphical user interface (GUI) via a personal computer, mobile computingdevice, personal data assistant, smart phone, or the like.

FIG. 6A shows a graph 600 a of a level of light produced by a lightsource over time during a first part of a year, according to onenon-limiting illustrated embodiment.

In particular, the level of light output by the light source is shownalong the Y-axis, while time is shown along the X-axis. In a first dailycycle 602 a, the light source is turned ON at 604 a to produce light ata first level (e.g., relatively high) 606 a. The light source may beturned ON in response detecting a first event or condition, for examplethat a level of light in the ambient environment has fallen below somedefined threshold (e.g., level of light corresponding to dusk or “duskthreshold”). The first level 606 a of light is maintained untildetection of a second event or condition. For example, the first level606 a of light may be maintained until a real world time at theparticular location reaches some defined first adjustment time (e.g., 10PM). Thus, the first level 606 a of light may be maintained for a firstduration 608 a, which may, for example, be the duration of time betweensensing dusk and a defined or set time (e.g., 10 PM). The level of lightproduced by the light source is then adjusted at 610 a to produce asecond, lower level 612 a. The second level of light 612 a may be deemedsufficient to provide some level of lighting when the amount of traffic(e.g., foot or vehicle traffic) in the location is expected to be small,while still being efficient.

The second level 612 a of light may be maintained until a detection of athird event or condition. For example, the second level 612 a of lightmay be maintained until a real world time at the particular locationreaches some defined second adjustment time (e.g., 6 AM). Thus, thesecond level 612 a of light may be maintained for a second duration 614a, which may, for example, be the duration of time between 10 PM and 6AM. The level of light produced is then adjusted at 616 a to produce athird level 606 a of light, higher than the second level 612 a. Whileillustrated as equal to the first level 606 a, the third level may behigher or lower than the first level 606 a.

The level of light is maintained until detection of a fourth event orcondition. For example, the third level of light 606 a may be maintaineduntil a level of light in the ambient environment has increased to orabove some defined threshold (e.g., level of light corresponding to dawnor “dawn threshold”). Thus, the level of light may be maintained for athird duration 618 a, which may, for example, be the duration of timebetween the set time 6 AM and sensing dawn. As illustrated, this patternmay repeat for additional daily cycles, although the length of thedurations 608 a, 618 a may gradually change, for example as the time ofsunrise and sunset varies changes throughout the year.

The thresholds (e.g., turn ON or dusk threshold; turn OFF or dawnthreshold) may be factory set or may be user configurable, set based onuser input received via a user interface (e.g., buttons, switches,dials, potentiometers, shorting jumpers, wired or wirelesscommunications ports, or via power line carrier control) of theluminaire. The adjustment times 610 a, 616 a at which the level of lightis adjusted may be factory set or may be user configurable, set based onuser input received via a user interface (e.g., buttons, switches,dials, potentiometers, shorting jumpers, wired or wirelesscommunications ports, or via power line carrier control) of theluminaire. Such user input may, for instance, indicate a fixed realworld time for the second and third thresholds.

FIG. 6B shows a graph 600 b of a level of light produced by a lightsource over time during a second part of a year, according to onenon-limiting illustrated embodiment.

Times or durations corresponding to those of FIG. 6A are called outusing the same reference numerals but with the lower case letter “b”instead of the lower case letter “a” used in FIG. 6A. The pattern issimilar to that illustrated in FIG. 6A, however the first threshold(e.g., turn ON or dusk threshold) is reached at an earlier time 604 b inthe daily cycle while the fourth threshold (e.g., turn OFF or dawnthreshold) is reached at a later time 620 b in the daily cycle to thechange in the amount of daylight hours in the daily cycle. Hence, thefirst duration 608 a at the relatively high first level 606 b is longerthan that illustrated in FIG. 6A, starting earlier. Likewise, the thirdduration 618 b at the relatively high third level 606 b is longer thanthat illustrated in FIG. 6A, ending later. Such is in response to theamount of daylight in the daily cycle 602 b being shorter than thatillustrated in FIG. 6A. Thus, FIG. 6A may represent summer in theNorthern Hemisphere, while FIG. 6B may represent winter in the samelocation.

FIG. 6C shows a graph 600 c of a level of light produced by a lightsource over time during the first part of a year with dusk and dawnsensing thresholds set to be reached earlier and later in a daily cycle,respectively, according to one non-limiting illustrated embodiment.

Times or durations corresponding to those of FIGS. 6A and 6B are calledout using the same reference numerals but with the lower case letter “c”instead of the lower case letter “a” or “b” used in FIGS. 6A and 6B,respectively. The pattern is similar to that illustrated in FIG. 6A,however the threshold at which a level of light corresponding to dusk issensed is adjusted downward or reduced such that dusk is sensed at anearlier time 604 c in a daily cycle (e.g., 5:00 PM), while the thresholdat which a level of light corresponding to dawn is sensed is adjustedupward or increased such that dawn is sensed at an earlier time 620 c inthe daily cycle (e.g., 5:30 AM). Additionally, the time 610 c at whichthe level of illumination is reduced is set to occur later, and the time616 c at which the level of illumination is raised is set to occurearlier than in FIG. 6A. Consequently, first and third durations 608 c,618 c at the high level 606 c are longer than that illustrated in FIG.6A. As noted above, the times 610 c, 616 c at which the level of lightis adjusted may be factory set or may be user configurable, set based onuser input received via a user interface (e.g., buttons, switches,dials, potentiometers, shorting jumpers, wired or wirelesscommunications ports, or via power line carrier control) of theluminaire.

FIG. 6D shows a graph 600 d of a level of light produced by a lightsource over time during the second part of a year, according to onenon-limiting illustrated embodiment.

Times or durations corresponding to those of FIGS. 6A-6C are called outusing the same reference numerals but with the lower case letter “d”instead of the lower case letter “a” “b” or “c” used in FIGS. 6A-6C,respectively. The pattern is similar to that illustrated in FIG. 6A,however the third threshold has been changed such that the first andthird durations 608 d, 618 d are of unequal lengths with respect to oneanother. For example, the third threshold may be set to occur at a latertime 616 d (e.g., 8 AM), as compared to an earlier time 616 a (e.g., 6AM). As previously noted, the third threshold may be user configurable,set based on user input received via a user interface (e.g., buttons,switches, dials, communications port) of the luminaire.

FIGS. 7A-7C show a high level method 700 of operating an illuminationsystem to provide illumination in an area, such as a secured area,according to one non-limiting illustrated embodiment.

The method 700 starts at 702. For example, the method 700 may start uponapplication of power to the luminaire or turning ON of a switch orrelay, either locally or remotely located from the illumination system.The illumination system may, for example, be controlled remotely via oneor more communications channels, for example one or more extranets,intranets, or the Internet, or via one or more cellular, plain oldtelephone service (POTS), or other telecommunications channels ornetworks.

At 704, at least one component of the illumination system receives oneor more signals indicative of a current location of the illuminationsystem. Optionally, the at least one component also receives signalsindicative of the current date and/or current time. For example, acontrol subsystem may include a receiver configured to receive GPSsignals from GPS satellites, cellular network signals from cellular basestations, wireless networks signals, landline signals, radio signals, orthe like.

At 706, at least one component of the illumination system determines acurrent location of the illumination source. For example, an integralcontrol subsystem may include a microcontroller operable to decode astream of data, including latitude and longitude data from a receiversuch as a GPS receiver, to determine the current location of theillumination system. The microcontroller may then store informationindicative of the current location in a non-volatile memory or storagemedium. As another example, the microcontroller may be operable todetermine the current location based on signals received fromgeographically dispersed terrestrial sources, using triangulation orother algorithms or approaches (e.g., signal time of flight). Forinstance, the microcontroller may be operable to determine the locationby querying the receiver which is configured to acquire signals from twoor more cellular network radio towers or base stations. One cellularnetwork signal may also be used if the location or identity of the toweris encoded into the transmitted signal.

At 708, at least one component of the illumination system determines thecurrent time. For example, a microprocessor may convert a current timeindicated in the received signal from one format to another. Forinstance, the microprocessor may convert a Universal Coordinate Time(UCT) or Greenwich Mean Time (GMT) representation to a local time basedon the determined location of the illumination system. Such may accountfor whether day light saving time is, or is not in effect, at thedetermined location. Alternatively, or additionally, the illuminationsystem may include a real time clock or a solar clock. The clock may beinitially set by user input or by synchronizing the clock based upon GPSsignals, cellular network signals, radio signals, (e.g., UCT signal) orother signals received by the receiver, and may be updated orsynchronized from time-to-time (e.g., periodically or aperiodically)based on such signals.

At 710, at least one component of the illumination system detects thelevel of light in the ambient environment. The illumination system orretrofit may include an ambient light sensor (e.g., photosensor, cadmiumsulfide cell, photodiode, phototransistor, ambient light sensorintegrated circuit) that is responsive to a level of light in theambient environment (e.g., daylight or ambient light). The controllersubsystem may include a microcontroller and a non-volatile memory orstorage medium into which the sensor periodically stores sensed levelsof light. An integral subsystem controller of the illumination systemmay query registers to retrieve stored data representing the currentlevel of light. Alternatively, the sensor may be directly controlled bythe integral subsystem controller which may receive real-timeindications of levels of light from the sensor.

At 712, the illumination system determines whether the detected level oflight is at equal or less than (i.e., equals or below) to a firstthreshold. The first threshold may represent a level of light at whichthe illumination is to be turned ON (e.g., dusk threshold). If thedetected level of light is less than or below the first threshold,control passes to 714. Otherwise, control passes to 724.

At 714, at least one component of the illumination system validates theresult of the comparison of the detected level of light in the ambientenvironment to the first threshold with respect to at least one expectedcondition. In other words, the component validates the detection of theoccurrence of an event or condition (e.g., dusk). For example, themicroprocessor may compare an actual level of illumination detected toan expected level of illumination for the particular location, at thecurrent time and current date. Also for example, the microprocessor cancompare the actual time the event (e.g., dusk) occurred or was detectedto an expected or predicted time of the event at the particular locationand current date. Such approaches are may identify malfunctioningcomponents, unintentional interference or even intentional tampering.Detecting such aberrations facilitates preventing or detecting falsepositive or false negative results. Such approaches are discussed indetail below, in reference to FIGS. 8 and 9.

At 716, at least one component of the illumination system determineswhether the detection was valid. If the detection was valid controlpasses to 722. If the detection was not valid or was invalid, controlpasses to 718.

At 718, at least one component of the illumination system produces anotification or alert. The notification or alert may take many forms. Anaural alert may include a wide range of alarms sounds produce via one ormore speakers, sirens, klaxons, either commonly located with theillumination system or remote therefrom. The aural alert may be providedat a user selectable volume. A visible alert may include flashing,blinking or strobing one or more lights located commonly with theillumination system, and/or remotely therefrom. Such may a flashingpattern executed by the illumination source itself. A data alert may betransmitted through a cellular network, a wireless network, a landline,or other communications networks or channels. The data alert may be sentto a security center, to a multimedia center which initiates videocapture of the vicinity, or to the personal computer or smart phone of aperson responsible for the area illuminated by the illumination system.Such an alert system may satisfy a governmental or other requirement orcondition for security lighting. Further, on the occurrence of anaberration or fault, whether unintentional or intentional, the controlsystem may default to an ON condition, at the brightest level ofillumination.

Optionally at 720, at least one component of the illumination system mayadjust a level of output of the at least one illumination source. Forexample, the microprocessor may increase the output of the illuminationsources to a relatively high level, which may be at or proximate ahighest output level of the illumination sources. Such may be particularappropriate where failure of a component (e.g., sensor) or tampering maybe suspected based on the determination that the detection was notvalid. For example, such may be a particularly appropriate responsewhere a high level of light is detected in the ambient environment at atime when a low level is expected since such may indicate that someoneis deliberately shining a light at the sensor to trick the illuminationsystem. Control then returns to 704, and the method 700 is repeated, ormay be called again by a calling routine or program.

In response to determining that a detected level of light in the ambientenvironment is equal to or below a first threshold (e.g. dusk threshold)at 712 and determining the detected condition is valid at 716, at leastone component of the illumination system turns ON the at least oneillumination source at 722. For example, the microcontroller may controla power supply or other circuit to cause electrical power to be suppliedto one or more of the illumination sources. For instance, depending onthe particular type of light source, the control mechanism, may rectifyand/or reduce a voltage, current, or duty cycle of the electrical powervia any variety of electrical or electronic circuitry (e.g., rheostat,DC/DC converter, other power regulator). The illumination sources may,for example, be turned ON to a relatively high level, for instanceproximate to the full rated output of the illumination sources.Additionally, or alternatively, all or a large number of the commonlylocated illumination sources may be turned ON, to provide the desiredlevel of illumination. The method may then continue at 724.

At 724, at least one component of the illumination system determineswhether the level of illumination should be adjusted. For example, themicroprocessor may determine whether the real world time is equal to adefined first adjustment time. The first adjustment time may be a useror otherwise defined time at which the level of illumination produced bythe at least one light source is programmed or configured to be reduced.For instance, a user or other individual or entity may determine thatthe amount of traffic (e.g., foot traffic) in a retail parking lot or apublic park is minimal sometime after the retail hours (e.g., 11 PM).Thus, there is generally no need for maintaining illumination at fulloutput. Thus, a time for decreasing illumination levels may be set,using the real world local time of the location. Such not only resultsin energy efficient operation, but does so using an easy to understand,intuitive user interface making it more likely that this feature isused, and used correctly.

If the first adjustment time has been reached, the level of illuminationis adjusted at 726. For example, at least one component of theillumination system decreases or reduces the amount of illuminationprovided by the at least one illumination source. For instance, themicrocontroller may control a power supply or other circuit to causeelectrical power to be supplied to one or more of the illuminationsources. The amount of power delivered to respective ones of theilluminations sources may be reduced, for instance using a shorter dutycycle in a pulse width modulated system. Alternatively, or additionally,fewer of the illumination sources may be powered or turned ON, some ofthe illumination sources being turned OFF to reduce the cumulativeillumination level output by the illumination sources.

In such an embodiment, a first number of illumination sources arepowered to achieve a relatively high level of illumination, while asecond number of illumination sources, less than the first, are poweredto produce the relatively lower, yet non-zero level of illumination.When operated in this fashion, at least one component of theillumination may vary the particular illuminations sources that arepowered and those which are not, for example from daily cycle to dailycycle. Such may cause any wear to be distributed relatively evenlyacross the total number of illumination sources. This may help toachieve relatively uniform illumination output between the variousillumination sources, particularly where the output varies with use overtime. This may also reduce the number of times that any given set ofillumination sources need to be serviced, since this approach will causeall of the illumination sources to tend to reach the end of their usefullives around the same time. The variation may be or may be variedrandomly, for example using a random number generator to select whichones of the illumination sources will be ON and which OFF to achieve thelower level of illumination.

At 728, at least one component of the illumination system determineswhether motion is sensed in the illuminated area. Such may employ any ofa variety of motion sensors (e.g., photosensor, cadmium sulfide cell,photodiode, phototransistor, ambient light sensor integrated circuit,Videocon, CCD array).

If motioned is sensed, control passes to 730 where a timer is started.The timer is used to control how long (e.g., 1 minute, 5 minutes, 15minutes) an elevated illumination will be provided in response tosensing motion on the illuminated area. The timer may be integral to themicroprocessor or may be a distinct timer.

At 732, at least one component of the illumination system adjusts theoutput of the illumination source. For example, in response to sensingmotion, the microprocessor may cause an output of the at least one lightsource to be increased. For instance, the microcontroller may control apower supply or other circuit to cause electrical power to be suppliedto one or more of the illumination sources. The amount of powerdelivered to respective ones of the illuminations sources may beincreased, for instance using a longer duty cycle in a pulse widthmodulated system. Alternatively, or additionally, a greater number ofthe illumination sources may be powered or turned ON, to increase thecumulative illumination level output by the illumination sources.

At 734, at least one component of the illumination system determineswhether the timer has reached the first defined time, repeating a waitloop until the defined time condition is reached. Upon reaching thedefined time, at least one component of the illumination system adjuststhe output of the illumination sources at 736, for example reducing theoutput back to the relatively low, non-zero, level of illumination thatwas being provided before the motion was sensed. Again, themicrocontroller may control a power supply or other circuit to causeelectrical power to be supplied to one or more of the illuminationsources. The amount of power delivered to respective ones of theilluminations sources may be reduced, for instance using a shorter dutycycle in a pulse width modulated system. Alternatively, or additionally,fewer of the illumination sources may be powered or turned ON, some ofthe illumination sources being turned OFF to reduce the cumulativeillumination level output by the illumination sources. At 738, the timeris reset in preparation for future use.

At 740, at least one component of the illumination system determineswhether the level of illumination should be adjusted. For example, themicroprocessor may determine whether the real world time is equal to adefined second adjustment time. The second adjustment time may be a useror otherwise defined time at which the level of illumination produced bythe at least one light source is programmed or configured to beincreased. For instance, a user or other individual or entity maydetermine that the amount of traffic (e.g., foot traffic) in a retailparking lot is increases sometime before the retail hours (e.g., 8 AM)or sometime before dawn (e.g., 5 AM-9 AM). Consequently, there isgenerally a need for maintaining illumination at full output. Thus, atime for increasing illumination levels may be set, using the real worldlocal time of the location. Such not only results in energy efficientoperation, but does so using an easy to understand, intuitive userinterface making it more likely that this feature is used, and usedcorrectly.

If the second adjustment time has been reached, the level ofillumination is adjusted at 742. For example, at least one component ofthe illumination system increases the amount of illumination provided bythe at least one illumination source. For instance, the microcontrollermay control a power supply or other circuit to cause electrical power tobe supplied to one or more of the illumination sources. The amount ofpower delivered to respective ones of the illuminations sources may beincreased, for instance using a longer duty cycle in a pulse widthmodulated system. Alternatively, or additionally, a greater number ofthe illumination sources may be powered or turned ON to increase thecumulative illumination level output by the illumination sources. Insuch an embodiment, a first number of illumination sources are poweredto achieve a relatively high level of illumination, while a secondnumber of illumination sources, less than the first, are powered toproduce the relatively lower, yet non-zero level of illumination.

At 744, at least one component of the illumination system determineswhether the detected level of light is equal to or greater than a secondthreshold. The second threshold may represent a level of light at whichthe illumination is to be turned OFF (e.g., dawn threshold). If thedetected level of light is at least equal to the second threshold,control passes to 746. Otherwise, control returns to 704 and the method700 may repeat.

At 746, at least one component of the illumination system validates theresult of the comparison of the detected level of light in the ambientenvironment to the second threshold with respect to at least oneexpected condition. In other words, the component validates thedetection of the occurrence of an event or condition (e.g., dawn). Forexample, the microprocessor may compare an actual level of illuminationdetected to an expected level of illumination for the particularlocation, at the current time and current date. Also for example, themicroprocessor can compare the actual time of the event or detectionthereof to an expected or predicted time of the event (e.g., dawn) atthe particular location and current date. Such approaches are mayidentify malfunctions, unintentional interference with, or evenintentional tampering. Identifying such aberrations may facilitate inpreventing or detecting false positive or false negative results. Suchapproaches are discussed in detail below, in reference to FIGS. 8 and 9.

At 748, at least one component of the illumination system determineswhether the detection was valid. If the detection was valid controlpasses to 754. If the detection was not valid or was invalid, controlpasses to 750.

At 750, at least one component of the illumination system produces anotification or alert. As previously discussed, the notification oralert may take many forms, which will not be repeated here in theinterest of brevity.

Optionally at 752, at least one component of the illumination system maymaintain or adjust a level of output of the at least one illuminationsource. For example, the microprocessor may cause the output of theillumination sources to be maintained or increased to a relatively highlevel, at or proximate a highest output level of the illuminationsources. Such may be particular appropriate where failure of a component(e.g., sensor) or tampering may be suspected based on the determinationthat the detection was not valid. Control then returns to 704, and themethod 700 is repeated, or may be called again by a calling routine orprogram.

In response to determining that a detected level of light in the ambientenvironment is equal to or greater than a second threshold (e.g. dawnthreshold) at 744 and determining the detected condition is valid at748, at least one component of the illumination system turns OFF the atleast one illumination source at 754. For example, the microcontrollermay control a power supply or other circuit to cause cessation ofelectrical power being supplied to one or more of the illuminationsources. Control may pass to 704, and the method 700 repeated.

The method 700 may be implemented to automatically turn ON and turn OFFillumination in response to detected ambient conditions, and toselectively increase and decrease the level of illumination at selectedtimes and/or in response to detection of motion. Such may reduce, oreven eliminate, the need to train, learn or adjust to the lightingconditions at a current location, or may eliminate that training,learning, or adjustment to refinements related to artificial lightsources or conditions at the location. Thus, for example, a singleretrofit or integral control subsystem may be sold and/or installed inlocations at widely different latitudes (e.g., Miami, Fla. and Nome,Ak.) with little or no self training required by the system. Notably,the variation in the length of daylight/nighttime is more extreme thefarther a location is from the Equator. Such retrofit or integralcontrol subsystem can automatically accommodate to the significantdifferences between locales. The microcontroller may store the time(e.g., time relative to turning ON, time indicated by real time clock)in the non-volatile storage media. The method 700 may advantageouslyinclude verification of the detection of conditions or events, allowingdetection of suspected instances of unintentional failure of one or morecomponents, unintentional interference and/or intentional tampering withone or more components.

FIG. 8 shows a method 800 of performing validating a detection of acondition or event, according to one illustrated embodiment. The method800 may be useful in performing the validating 714, 746 (FIGS. 7A-7C) ofthe method 700.

At 802, at least one component of the illumination system determines thelevel of light expected in the ambient environment for the determinedcurrent location, current date and/or the current time. The currentlocation may be derived from one or more signals received from anexternal source, for instance from one or more GPS satellites orcellular communications base stations. The current date and/or currenttime may likewise be derived from one or more signals received from anexternal source, or alternatively, or additionally be derived from acalendar and/or real world time clock maintained by the illuminationsystem. The illumination system may from time to time synchronize thecalendar and/or real world time clock maintained thereby with thecurrent date and/or time indicated in the signal(s) received from theexternal source(s).

A microcontroller may access lookup tables stored in non-volatile memoryto determine the expected level of light based on the determined currentlocation, current date and/or the current time. The lookup tables mayinclude data representing solar midnight and solar noon, and/or timesfor sunrise and sunset. Alternatively, or additionally, themicrocontroller may analytically calculate the expected level of lightinformation based on the determined current location, current dateand/or the current time using one or more formulas. The microcontrollermay also adjust the expected level of illumination based on whether daylight savings applies in the particular location. The microcontrollermay even adjust the expected level of illumination based on current orforecasted weather conditions, which may be indicated in the receivedsignals. As a further alternative, the microcontroller may wirelesslyquery a remote database via a wireless network with the determinedcurrent location, current date and/or the current time, to obtain theexpected level of light.

At 804, at least one component of the illumination system determineswhether a detected level of light in the ambient environment is within adefined threshold of an expected level of light in the ambientenvironment for the determined current location, current date and/or thecurrent time. In other words, the component, for instance themicroprocessor, validates the detection by ensuring that the actuallevel of light detected in the ambient environment is what is expectedor predicted for the time of day, at the time of year and the particularlocation. Otherwise, the detection may be the result of an aberrantcondition, for example a failure of a component or intentional tamperingor unintentional interference.

The defined threshold provides a margin of variability in expected lightlevel in the ambient environment, compensating for fluctuations due tohigh light pollution, clouds, phases of the moon, and other naturalcauses of variation in nighttime levels of light. In some instances itmay be useful to set the defined threshold to detect unwanted coveringof the ambient light sensors, such as by a hand, bag or dark plastic orthe shinning of some other light source at the sensor. Thus, theillumination system sensitivity may be adjusted to differentiate betweennatural causes of changing light levels and the actions of perpetratorsseeking to manually defeat the purpose of the illumination system.

So, at 804, the illumination system is essentially determining whetherthe determination or measurement of ambient light conditions made isconsistent with what is expected for the particular current locationand/or current date and/or time. If the detected level of light in theambient environment is within a defined threshold of an expected levelof light in the ambient environment, the detection is identified asvalid at 806, and if not the detection is identified as not valid orinvalid at 808.

FIG. 9 shows a method 900 of performing validating a detection of acondition or event, according to another illustrated embodiment. Themethod 900 may be useful in performing the validating 714, 746 (FIGS.7A-7C) of the method 700.

At 902, at least one component of the illumination system determines anexpected time of day at which a particular trigger event or condition(e.g., light levels associated with dusk and/or dawn) is predicted tooccur for the determined current location, current date and/or thecurrent time. The current location may be derived from one or moresignals received from an external source, for instance from one or moreGPS satellites or cellular communications base stations. The currentdate and/or current time may likewise be derived from one or moresignals received from an external source, or alternatively, oradditionally be derived from a calendar and/or real world time clockmaintained by the illumination system. The illumination system may fromtime to time synchronize the calendar and/or real world time clockmaintained thereby with the current date and/or time indicated in thesignal(s) received from the external source(s).

The microcontroller may access lookup tables stored in non-volatilememory or storage media to determine the expected level of light basedon the determined current location, current date and/or the currenttime. The lookup tables may include data representing solar midnight andsolar noon, and/or times for sunrise and sunset. Alternatively, oradditionally, the microcontroller may analytically calculate theexpected time information based on the determined current location,current date and/or the current time using one or more formulas. Themicrocontroller may also adjust the expected time based on whether daylight savings time is in effective or applicable in the particularlocation. The microcontroller may even adjust the expected time based oncurrent or forecasted weather conditions, which may be indicated in thereceived signals. As a further alternative, the microcontroller maywirelessly query a remote database via a wireless network with thedetermined current location, current date and/or the current time, toobtain the expected time.

At 904, at least one component of the illumination system determineswhether a detected time at which the event or condition occurred or wassensed in the ambient environment is within a defined threshold of theexpected time that the event or condition was predicted to occur for thedetermined current location, current date and/or the current time. Inother words, the component, for instance the microprocessor, validatesthe detection by ensuring that the actual time that the event orcondition occurred or was sensed is what is expected for the time ofday, at the time of year and the particular location. Otherwise, thedetection may be the result of an aberrant condition, for example afailure of a component or intentional tampering or unintentionalinterference.

The defined threshold provides a margin of variability in expected time,compensating for fluctuations due to high light pollution, clouds,phases of the moon, and other natural causes of variation in nighttimelevels of light. In some instances it may be useful to set the definedthreshold to detect unwanted covering of the ambient light sensors, suchas by a hand, bag or dark plastic or the shinning of some other lightsource at the sensor. Thus, the illumination system sensitivity may beadjusted to differentiate between natural causes of changing lightlevels and the actions of perpetrators seeking to manually defeat thepurpose of the illumination system.

So, at 904, the illumination system is essentially determining whetherthe determination or measurement of ambient light conditions made isconsistent with what is expected for the particular current locationand/or current date and/or time. If the detected time that the event orcondition actually occurred is within a defined threshold of an expectedtime that the event or condition was predicted to occur, the detectionis identified as valid at 906, and if not the detection is identified asnot valid or invalid at 908.

FIG. 10 shows a method 1000 of operating a retrofit or integral controlsubsystem to determine a location of the illumination system based atleast in part on GPS data from GPS satellites and to determine anexpected level of light based at least in part on the determinedlocation, according to one non-limiting illustrated embodiment. Themethod 1000 may be employed with the method 700 (FIGS. 7A-7C).

At 1002, a receiver receives signals from GPS satellites. The receivermay employ a passive or active antenna, although signal reception issignificantly better with active antennas when compared to passiveantennas. The receiver synchronizes with and receives information fromand about at least one satellite. Each GPS satellite transmits the date,time, the satellite's orbit information, and an orbit almanac of theother GPS satellites. While date and time may be acquired from a singlesatellite, determination of a static location typically requiressynchronization with at least three GPS satellites. Notably, the GPSreceiver may be an integral part of the illumination system or even theluminaire or may be separate and distinct therefrom.

At 1004, the retrofit or integral control subsystem determines at leasta current latitude of the illumination system from the received signals.Determining latitude may be particularly important when compensating fordifferences in lengths of days and lengths of nights as a location ofinterest moves further away from the equator. The retrofit or integralcontrol subsystem determines the latitude of the illumination system bytriangulating the signals received from multiple GPS satellites.

Optionally, at 1006, the retrofit or integral control subsystemdetermines a current longitude of the illumination system from thereceived signals. Determining latitude and/or longitudinal allowscontrol subsystems to be advantageously manufactured without anyknowledge of or regard for the particular locations where those systemsmay be installed.

Optionally, at 1008, the retrofit or integral control subsystemdetermines whether daylight savings applies for the particular locationand date. The control subsystem may use a lookup table which may includeinformation regarding the time zones of continents, countries, states orother geographical or political boundaries. The lookup table may, forexample, produce an offset from coordinated universal time (UTC) basedupon inputs of latitude, longitude, and the date of the request.

At 1010, the retrofit or integral control subsystem determines thecurrent time from the received signals. The control subsystem determinesthe current time by parsing the data stream output from the GPSreceiver.

Optionally, at 1012, the retrofit or integral control subsystem updatesthe real time clock. Common electronics use quartz based real timeclocks because quartz crystal-based clocks are cheaper to manufacturethan the more precise time keeping alternatives. The determined currenttime from the received signals may be used to update the real time clockof the illumination system.

The method 1000 may be integrated with the method 700, method 800,method 900 and/or any of the other previously described methods.

FIG. 11 shows a method 1100 of operating a retrofit or integral controlsubsystem to determine a current location of a lighting system based atleast in part on signals from one or more cellular base stations, and todetermine an expected level of light based at least in part on thedetermined location, according to one non-limiting illustratedembodiment. The method 1100 may be employed with the method 700 (FIGS.7A-7C).

At 1102, a cellular communications receiver receives signals from one ormore cellular base stations. The received signals may includeinformation identifying the carrier, the signal strength, the state andcounty of the base station, and general handshaking instructions for thereceiving device to follow.

At 1104, the retrofit or integral control subsystem determines at leasta current latitude of the illumination system from the received signals.The cellular base stations track the locations of cellularreceivers/transceivers using triangulation or other methods. The one ormore cellular base stations may transmit latitude coordinate of theillumination system to the receiver upon receipt of a proper query tothe base station. Alternatively, the retrofit or integral controlsubsystem may perform the triangulation or other position estimatingalgorithm based on signals received from two or more geographicallydisparate cellular base stations. Notably, the cellular communicationsreceiver may be an integral part of the illumination system or even theluminaire or may be separate and distinct therefrom.

Optionally, at 1106, the retrofit or integral control subsystemdetermines a current longitude coordinate of the illumination system.For example, the retrofit or integral control subsystem may transmit aquery to the one or more cellular base stations and may decode the replyreceived from the one or more cellular base stations. Determininglatitude and/or longitudinal allows control subsystems to beadvantageously manufactured without any knowledge of or regard for theparticular locations where those systems may be installed.

Optionally, at 1108, the retrofit or integral control subsystemdetermines whether daylight savings applies for the particular locationand date. The control subsystem may use a lookup table which may includeinformation regarding the time zones of continents, countries, states orother geographical or political boundaries. The lookup table may, forexample, produce an offset from coordinated universal time (UTC) basedupon inputs of latitude, longitude, and the current date.

At 1110, the retrofit or integral control subsystem determines thecurrent time from the received signals. The control subsystem determinesthe current time by decoding the stream of data transmitted by thecellular base stations. The time may already be adjusted for daylightsavings time, the time may be in UTC format, or the time may be adjustedfor the location serviced by the cellular base station.

Optionally, at 1112, the retrofit or integral control subsystem updatesthe real time clock. Common electronics use quartz based real timeclocks because quartz crystal-based clocks are cheaper to manufacturethan the more precise time keeping alternatives. The determined currenttime from the received signals may be used to update the real time clockof the illumination system.

The method 1100 may be integrated with the method 700, method 800,method 900 and/or any of the other previously described methods.

FIG. 12 shows a low level method 1200 of operating a control subsystemof an illumination system to produce a notification, according to onenon-limiting illustrated embodiment. The method 1200 may be employedwith the method 700 (FIGS. 17A-17C).

At 1202, at least one component of the illumination system transmits analert over one or more communications channels. The employedcommunications channel may take a variety of forms. The data-based alertmay take the form of an SMS, text message, or email message over acellular network. The illumination system may transmit the alert byutilizing the communications protocols of facsimile or DSP over alandline to transmit an alert to a server, telephone, or fax machine.Alternatively, the illumination system may transmit an alert over awireless network, such as a LAN, WAN, or MAN. The alert may be directedto a central system controlling several illumination systems, a personalcomputer, or an automated system which initiates video recording of thearea proximate to the illumination device.

At 1204, at least one component of the illumination system illuminatesan alert at the luminaire and/or remotely therefrom. The illuminationsystem may illuminate one or more lights of uniform or differing colors.The illumination system may illuminate the lights in an alarmingpattern, such as rapid flashing, to indicate a error or problem hasoccurred.

At 1206, at least one component of the illumination system produces anaural alert at the luminaire and/or remotely therefrom. The aural alertmay take on a variety of forms. For example, the alert may be arecording which repeats the phrase “an error has been detected.” Asanother example, the alert may be an alarming sound such as a siren,klaxon, repeated horn honks, or a series of chimes that gradually growlouder.

FIG. 13 shows a high level method 1300 of operating a control system ofan illumination system to provide illumination, according to onenon-limiting illustrated embodiment.

At 1302, at least one component of the illumination system receives oneor more signals indicative of a current location of the illuminationsystem. Optionally, the at least one component also receives signalsindicative of the current time. For example, an integral controlsubsystem may include a receiver configured to receive GPS signals,cellular network signals, wireless networks signals, landline signals,radio signals, or the like.

At 1304, at least one component of the illumination system determinesthe location of the illumination source. The illumination system mayinclude an integral control subsystem that include a microcontrollerconfigured to decode a stream of data, including latitude and longitudedata from a receiver such as a GPS receiver, to determine the locationof the illumination system. The microcontroller may then store thelocation in a non-volatile memory. As another example, themicrocontroller may be operable to determine the location by querying areceiver which is configured to acquire latitude and longitude data fromcellular network radio towers.

At 1306, at least one component of the illumination system determineswhether day light saving times applies at a current location. Theillumination system may include a real time or solar clock and/orcalendar. The clock may be initially set by user input or bysynchronizing the clock based upon GPS signals, cellular networksignals, radio signals, or other signals received by the receiver. Amicroprocessor of the illumination system may use a lookup table storedin a non-transitory storage medium or create a database query for thelocation and date to determine whether: 1) the location employees daylight savings time, and if so 2) whether day light savings time is ineffect on that date in at the location. Alternatively, themicroprocessor may wirelessly query a remote.

At 1308, at least one component such as a microprocessor of theillumination system converts time from one format (e.g., UCT, GMT) to alocal time format. Such may include accounting for time zone differencesbetween UCT or GMT and the time zone in which the location is located.Such may also include accounting for day light savings time if in effectfor the current location on the current date.

Optionally at 1310, at least one component of the illumination systemupdates or synchronizes an internal clock and/or calendar based oncurrent time and/or current date information received from one or moreexternal sources.

At 1312, at least one component of the illumination system validates thedetermined condition. For example, a microprocessor may determinewhether the detected level of light is within a threshold of an expectedor predicted level of light. The expected level of light may be basedupon the determined location of the illumination system on the Earth,the determined current date or season of the year, and/or the determinedcurrent time. Also for example, a microprocessor may determine whetheran actual time at which an event (e.g., dusk, dawn) occurred or wassensed is within a threshold of an expected time at which the event waspredicted to occur or be sensed. The threshold accommodates reasonabledifferences in actual conditions, for example, amount of cloud cover,phases of the moon, typical amounts of reflection associated withparticular areas (e.g. urban, suburban, rural).

At 1314, at least one component of the illumination system determines ifthe detected condition was determined to be valid. If the actual ordetected does not fall within the threshold of the expected, then thecondition is considered invalid, and control passes to 1316 where analert or notification is produced. Otherwise, control returns 1302 andthe method 1300 may repeat.

Also, for example, the various methods may include additional acts, omitsome acts, and/or may perform the acts in a different order than set outin the various flow diagrams. The use of ordinals such as first, secondand third does not necessarily imply a ranked sense of order, but rathermay only distinguish between multiple instances of an act or structure.

Also, for example, the foregoing detailed description has set forthvarious embodiments of the devices and/or processes via the use of blockdiagrams, schematics, and examples. Insofar as such block diagrams,schematics, and examples contain one or more functions and/oroperations, it will be understood by those skilled in the art that eachfunction and/or operation within such block diagrams, flowcharts, orexamples can be implemented, individually and/or collectively, by a widerange of hardware, software, firmware, or virtually any combinationthereof. In one embodiment, the present subject matter may beimplemented via one or more microcontrollers. However, those skilled inthe art will recognize that the embodiments disclosed herein, in wholeor in part, can be equivalently implemented in standard integratedcircuits (e.g., Application Specific Integrated Circuits or ASICs), asone or more computer programs executed by one or more computers (e.g.,as one or more programs running on one or more computer systems), as oneor more programs executed by on one or more controllers (e.g.,microcontrollers) as one or more programs executed by one or moreprocessors (e.g., microprocessors), as firmware, or as virtually anycombination thereof, and that designing the circuitry and/or writing thecode for the software and/or firmware would be well within the skill ofone of ordinary skill in the art in light of the teachings of thisdisclosure.

When logic is implemented as software and stored in memory, logic orinformation can be stored on any computer-readable medium for use by orin connection with any processor-related system or method. In thecontext of this disclosure, a memory is a computer-readable storagemedium that is an electronic, magnetic, optical, or other physicaldevice or means that non-transitorily contains or stores a computerand/or processor program. Logic and/or the information can be embodiedin any computer-readable medium for use by or in connection with aninstruction execution system, apparatus, or device, such as acomputer-based system, processor-containing system, or other system thatcan fetch the instructions from the instruction execution system,apparatus, or device and execute the instructions associated with logicand/or information.

In the context of this specification, a “computer-readable medium” canbe any element that can store the program associated with logic and/orinformation for use by or in connection with the instruction executionsystem, apparatus, and/or device. The computer-readable medium can be,for example, but is not limited to, an electronic, magnetic, optical,electromagnetic, infrared, or semiconductor system, apparatus or device.More specific examples (a non-exhaustive list) of the computer readablemedium would include the following: a portable computer diskette(magnetic, compact flash card, secure digital, or the like), a randomaccess memory (RAM), a read-only memory (ROM), an erasable programmableread-only memory (EPROM, EEPROM, or Flash memory), a portable compactdisc read-only memory (CDROM), and digital tape.

The various embodiments described above can be combined to providefurther embodiments. To the extent that they are not inconsistent withthe specific teachings and definitions herein, all of the U.S. patents,U.S. patent application publications, U.S. patent applications, foreignpatents, foreign patent applications and non-patent publicationsreferred to in this specification and/or listed in the Application DataSheet, including but not limited to U.S. Patent Publication No. US2009/0278474, published Nov. 12, 2009; U.S. Patent Publication No. US2009/0284155, published Nov. 19, 2009; U.S. Patent Publication No. US2010/0090577, published Apr. 15, 2010; U.S. Provisional PatentApplication No. 61/051,619 filed May 8, 2008; U.S. Provisional PatentApplication No. 61/052,924 filed May 13, 2008; U.S. Provisional PatentApplication No. 61/088,651 filed Aug. 13, 2008; U.S. Provisional PatentApplication No. 61/115,438 filed Nov. 17, 2008; U.S. Provisional PatentApplication No. 61/154,619 filed Feb. 23, 2009; U.S. Provisional PatentApplication No. 61/174,913 filed May 1, 2009; U.S. Provisional PatentApplication No. 61/180,017 filed May 20, 2009; U.S. Provisional PatentApplication No. 61/229,435 filed Jul. 29, 2009; U.S. Non-Provisionalpatent application Ser. No. 12/619,535, filed Nov. 16, 2009; U.S.Provisional Patent Application No. 61/295,519 filed Jan. 15, 2010; U.S.Non-Provisional patent application Ser. No. 12/769,956, filed Apr. 29,2010; U.S. Provisional Patent Application Ser. No. 61/333,983, filed May12, 2010; U.S. Provisional Patent Application Ser. No. 61/346,263, filedMay 19, 2010; Nonprovisional patent application Ser. No. 12/784,091,filed May 20, 2010; U.S. Nonprovisional patent application Ser. No.12/784,093, filed May 20, 2010; and U.S. Nonprovisional patentapplication Ser. No. 13/085,301, filed Apr. 12, 2011; are incorporatedherein by reference, in their entirety. Aspects of the embodiments canbe modified, if necessary, to employ systems, circuits and concepts ofthe various patents, applications and publications to provide yetfurther embodiments.

The above description of illustrated embodiments, including what isdescribed in the Abstract, is not intended to be exhaustive or to limitthe embodiments to the precise forms disclosed. Although specificembodiments and examples are described herein for illustrative purposes,various equivalent modifications can be made without departing from thespirit and scope of the disclosure, as will be recognized by thoseskilled in the relevant art. The teachings provided herein of thevarious embodiments can be applied to other contexts, not necessarilythe exemplary context of controlling operations of an illuminationsystem generally described above.

For example, while the illumination systems are generally describedabove as embodied in a luminaire, the control subsystem may controlmultiple luminaires. As used herein and in the claims, luminaire is usedin its broadest sense to refer to any lighting fixture or structure.While a single step adjustment downward and upward in the level ofillumination has been described and illustrated, illumination level maybe adjusted in multiple steps, or even continuously to gradually rampdownward some time after turning ON the light source, then eventuallyback upward some time before turning OFF the light source. Additionally,or alternatively, the embodiments described herein may be combined withmotion or proximity detecting, either as implemented by a luminairecontrol mechanism or by a retrofit or integral control subsystem.

The microcontroller 314, 514 or control system 406 may be programmableand may include one or more input ports (not illustrated) through whicha user can program the microcontroller 314, 514 or control system 406.For example, the time delays and the various illumination levels of thelight source may be programmed. The input port may include switchesand/or potentiometers that can be set to program the microcontroller314, 514 or control system 406. Alternatively, the input port mayinclude communications interface for the user to remotely program themicrocontroller 314, 514 or control system 406 whether through a wire orwirelessly. The input port may be the ambient light sensor which isconnected to the microcontroller 314, 514 or control system 406. Forexample, the microcontroller 314, 514 or control system 406 may beprogrammable optically via one or more images captured by an imagecapture device or imager (not illustrated). For instance, the imagesensor may capture images of printed barcode symbols, which encodeinformation used to set delay times and other parameters used by themicrocontroller 314, 514 or control system 406. The microcontroller 314,514 or control system 406 may also receive a one-bit input via the inputport to activate or deactivate the light source. For example, a binarybit of “0” turns OFF the light source 110 and a binary bit of “1” turnsON the light source.

Also for example, the control subsystem 312, 512, 406 may furtherinclude a communication device. The communication device may becommunicatively coupled to the microcontroller 314, 514 or controlsystem 406. The communication device may be further coupled to anexternal data network using protocols in compliance with any or all ofthe Ethernet, the RS-485 and wireless communication standards, such asthe IEEE 802.11 standards for example, or commercially or proprietarypower line carrier control standards. The communication device may beused to remotely program the microcontroller 314, 514 or control system406. Alternatively, the communication device may be used to transmitinformation from the control subsystem 312, 512 or control system 406 toa remote user or processor based system. For example, the communicationdevice may be used to transmit a notification signal from themicrocontroller 314, 514 or control system 406 indicative of turning ON,turning OFF, increasing or decreasing output from a light source. Thecommunication device may be used to transmit an actuation signal fromthe microcontroller 314, 514 or control system 406 to actuate a devicesuch as an alarm or an automatic door.

These and other changes can be made to the embodiments in light of theabove-detailed description. In general, in the following claims, theterms used should not be construed to limit the claims to the specificembodiments disclosed in the specification and the claims, but should beconstrued to include all possible embodiments along with the full scopeof equivalents to which such claims are entitled. Accordingly, theclaims are not limited by the disclosure.

I claim:
 1. A method of operating an illumination system including atleast one light source and at least one controller, the methodcomprising: from time-to-time, detecting a level of light in an ambientenvironment; comparing by the at least one controller the detected levelof light in the ambient environment to a first threshold; validating bythe at least one controller a result of the comparison of the detectedlevel of light in the ambient environment to the first threshold withrespect to at least one expected condition; and adjusting by the atleast one controller an output of the at least one light source if boththe detected level of light in the ambient environment at leastsatisfies the first threshold and the result of the comparison is validwith respect to the at least one expected condition.
 2. The method ofclaim 1 wherein validating a result of the comparison of the detectedlevel of light in the ambient environment to the first threshold withrespect to at least one expected condition includes: comparing by the atleast one controller an actual time at which the detected level of lightsatisfied the first threshold to an expected time when the level oflight is predicted to satisfy the first threshold for at least one of acurrent location or a current date; determining that the result of thecomparison is valid if the actual time at which the detected level oflight satisfied the first threshold is within a second threshold of theexpected time when the level of light is predicted to satisfy the firstthreshold for the at least one of the current location or the currentdate; or determining that the result of the comparison is invalid if theactual time at which the detected level of light satisfied the firstthreshold is not within the second threshold of the expected time whenthe level of light is predicted to satisfy the first threshold for theat least one of the current location or the current date.
 3. The methodof claim 1 wherein validating a result of the comparison of the detectedlevel of light in the ambient environment to the first threshold withrespect to at least one expected condition includes: comparing by the atleast one controller the detected level of light in the ambientenvironment to an expected level of light for at least one of a currentlocation, a current date or a current time; determining that the resultof the comparison is valid if the detected level of light in the ambientenvironment is within a second threshold of the expected level of lightfor the at least one of the current location, the current date or thecurrent time; or determining that the result of the comparison isinvalid if the detected level of light in the ambient environment is notwithin the second threshold of the expected level of light for the atleast one of the current location, the current date or the current time.4. The method of claim 3 wherein comparing the detected level of lightin the ambient environment to an expected level of light for at leastone of a current time or a current location includes comparing thedetected level of light to a value indicative of the expected level oflight for the current time at the current location.
 5. The method ofclaim 1 wherein from time-to-time, detecting a level of light in anambient environment includes continuously receiving a signal at the atleast one controller from an ambient light sensor which is part of theillumination system, the signal indicative of the level of light in theambient environment.
 6. The method of claim 1, further comprising:receiving a location signal at the at least one controller indicative ofthe current location; and determining by the at least one controller atleast one of an excepted level of light or an expected time at which thelevel of light is predicted to satisfy the first threshold based on thecurrent location identified by the location signal.
 7. The method ofclaim 6, further comprising: receiving a time signal at the at least onecontroller indicative of the current time.
 8. The method of claim 6wherein receiving a location signal indicative of the current locationincludes receiving the location signal from a global positioning systemreceiver.
 9. The method of claim 6 wherein receiving a location signalindicative of the current location includes receiving the signal from atleast one cellular communications system receiver.
 10. The method ofclaim 1 wherein adjusting an output of the at least one light source ifboth the detected level of light in the ambient environment at leastsatisfies the first threshold and the result of the comparison is validwith respect to the at least one expected condition includes turning theat least one light source ON if both the detected level of light in theambient environment is equal or less than a turn ON threshold and anactual time at which the detected level of light satisfied the firstthreshold is within a second threshold of the expected time when thelevel of light is predicted to satisfy the first threshold for the atleast one of the current location or the current date.
 11. The method ofclaim 1 wherein adjusting an output of the at least one light source ifboth the detected level of light in the ambient environment at leastsatisfies the first threshold and the result of the comparison is validwith respect to the at least one expected condition includes turning theat least one light source ON if both the detected level of light in theambient environment is equal or less than a turn ON threshold and thedetected level of light in the ambient environment is within the secondthreshold of the expected level of light for the current time at thecurrent location.
 12. The method of claim 1 wherein adjusting an outputof the at least one light source if both the detected level of light inthe ambient environment at least satisfies the first threshold and theresult of the comparison is valid with respect to the at least oneexpected condition includes turning the at least one light source OFF ifboth the detected level of light in the ambient environment is equal orgreater than a turn OFF threshold and an actual time at which thedetected level of light satisfied the first threshold is within a secondthreshold of the expected time when the level of light is predicted tosatisfy the first threshold for the at least one of the current locationor the current date.
 13. The method of claim 1 wherein adjusting anoutput of the at least one light source if both the detected level oflight in the ambient environment at least satisfies the first thresholdand the result of the comparison is valid with respect to the at leastone expected condition includes turning the at least one light sourceOFF if both the detected level of light in the ambient environment isequal or greater than a turn OFF threshold and the detected level oflight in the ambient environment is within the second threshold of theexpected level of light for the current time at the current location.14. The method of claim 1, further comprising: reducing the output ofthe at least one light source to a non-zero level when a first real timein a daily cycle is reached.
 15. The method of claim 14, furthercomprising: detecting motion at least proximate an area beingilluminated; and in response to the detecting motion, temporallyincreasing the output of the at least one light source.
 16. The methodof claim 15, further comprising: increasing the output of the at leastone light source when a second real time in the daily cycle is reached.17. The method of claim 16 when the result of the comparison is invalidwith respect to the at least one expected condition, further comprising:repeating at least the reducing and the increasing the output of the atleast one light source when the first and the second real times,respectively, are reached for a number of additional daily cycles. 18.The method of claim 16 wherein repeating at least the reducing and theincreasing the output of the at least one light source when the firstand the second real times, respectively, are reached for a number ofadditional daily cycles, further includes turning ON the at least onelight source at a time in a daily cycle that corresponds to dusk andturning OFF the at least one light source at a time in the daily cyclethat corresponds to dawn.
 19. The method of claim 1, further comprising:producing by the controller an external notification if the detectedlevel of light in the ambient environment is not within the secondthreshold of the expected level of light for the current time at thecurrent location.
 20. The method of claim 19, further comprising: inresponse to determining that the result of the comparison is invalid,causing the output of the at least one light source to be at leastproximate a highest level of the at least one light source.
 21. A systemto control illumination, the system comprising: at least one controllerthat: from time-to-time, receives a signal indicative of a level oflight in an ambient environment; compares the detected level of light inthe ambient environment to an expected level of light for at least oneof a current time or a current location; compares the detected level oflight in the ambient environment to a first threshold; validates aresult of the comparison of the detected level of light in the ambientenvironment to the first threshold with respect to at least one expectedcondition; and adjusts an output of the at least one light source ifboth the detected level of light in the ambient environment at leastsatisfies the first threshold and the result of the comparison is validwith respect to the at least one expected condition.
 22. The system ofclaim 21 wherein to validate a result of the comparison of the detectedlevel of light in the ambient environment to the first threshold withrespect to at least one expected condition, the at least one controller:compares an actual time at which the detected level of light satisfiedthe first threshold to an expected time when the level of light ispredicted to satisfy the first threshold for at least one of a currentlocation or a current date; determines that the result of the comparisonis valid if the actual time at which the detected level of lightsatisfied the first threshold is within a second threshold of theexpected time when the level of light is predicted to satisfy the firstthreshold for the at least one of the current location or the currentdate; or determines that the result of the comparison is invalid if theactual time at which the detected level of light satisfied the firstthreshold is not within the second threshold of the expected time whenthe level of light is predicted to satisfy the first threshold for theat least one of the current location or the current date.
 23. The systemof claim 21 wherein to validate a result of the comparison of thedetected level of light in the ambient environment to the firstthreshold with respect to at least one expected condition, the at leastone controller: compares the detected level of light in the ambientenvironment to an expected level of light for at least one of a currentlocation, a current date or a current time; determines that the resultof the comparison is valid if the detected level of light in the ambientenvironment is within a second threshold of the expected level of lightfor the at least one of the current location, the current date or thecurrent time; or determines that the result of the comparison is invalidif the detected level of light in the ambient environment is not withinthe second threshold of the expected level of light for the at least oneof the current location, the current date or the current time.
 24. Thesystem of claim 23 wherein the at least one controller compares thedetected level of light to a value indicative of an expected level oflight for the current time at the current location.
 25. The system ofclaim 21, further comprising: an ambient light sensor, wherein the atleast one controller continuously receives a signal from the ambientlight sensor, the signal indicative of the level of light in the ambientenvironment.
 26. The system of claim 21 wherein the at least onecontroller further receives a location signal indicative of the currentlocation; and determines at least one of an excepted level of light oran expected time at which the level of light is predicted to satisfy thefirst threshold based at least in part on the current locationidentified by the location signal.
 27. The system of claim 26 whereinthe at least one controller further receives a time signal indicative ofthe current time.
 28. The system of claim 26, further comprising: anantenna; and a global positioning receiver communicatively coupled tothe antenna to receive a global positioning signal from a number ofglobal positioning system satellites, wherein the at least onecontroller is communicatively coupled to the global positioning receiverto receive the location signal indicative of the current location. 29.The system of claim 26, further comprising: an antenna; and a cellularcommunications receiver communicatively coupled to the antenna toreceive a cellular communications signal from a number of cellularcommunications antennas, wherein the at least one controller iscommunicatively coupled to the cellular communications receiver toreceive the location signal indicative of the current location.
 30. Thesystem of claim 21 wherein to adjust the output of the at least onelight source if both the detected level of light in the ambientenvironment at least satisfies the first threshold and the result of thecomparison is valid with respect to the at least one expected conditionthe at least one controller turns the at least one light source ON ifboth the detected level of light in the ambient environment is equal orless than a turn ON threshold and an actual time at which the detectedlevel of light satisfied the first threshold is within a secondthreshold of the expected time when the level of light is predicted tosatisfy the first threshold for the at least one of the current locationor the current date.
 31. The system of claim 21 wherein to adjust theoutput of the at least one light source if both the detected level oflight in the ambient environment at least satisfies the first thresholdand the result of the comparison is valid with respect to the at leastone expected condition the at least one controller turns the at leastone light source ON if both the detected level of light in the ambientenvironment is equal or less than a turn ON threshold and the detectedlevel of light in the ambient environment is within the second thresholdof the expected level of light for the current time at the currentlocation.
 32. The system of claim 21 wherein to adjust the output of theat least one light source if both the detected level of light in theambient environment at least satisfies the first threshold and theresult of the comparison is valid with respect to the at least oneexpected condition the at least one controller turns the at least onelight source OFF if both the detected level of light in the ambientenvironment is equal or greater than a turn OFF threshold and an actualtime at which the detected level of light satisfied the first thresholdis within a second threshold of the expected time when the level oflight is predicted to satisfy the first threshold for the at least oneof the current location or the current date.
 33. The system of claim 21wherein to adjust the output of the at least one light source if boththe detected level of light in the ambient environment at leastsatisfies the first threshold and the result of the comparison is validwith respect to the at least one expected condition the at least onecontroller turns the at least one light source OFF if both the detectedlevel of light in the ambient environment is equal or greater than aturn OFF threshold and the detected level of light in the ambientenvironment is within the second threshold of the expected level oflight for the current time at the current location.
 34. The system ofclaim 21 wherein the at least one controller reduces the output of theat least one light source to a non-zero level when a first real time ina daily cycle is reached.
 35. The system of claim 34 wherein the atleast one controller further: detects motion at least proximate an areabeing illuminated; and in response to the detection of motion,temporally increases the output of the at least one light source. 36.The system of claim 35 wherein the at least one controller, further:increases the output of the at least one light source when a second realtime in the daily cycle is reached.
 37. The system of claim 36 whereinwhen the result of the comparison is invalid with respect to the atleast one expected condition, the at least one controller further:repeats at least the reducing and the increasing the output of the atleast one light source when the first and the second real times,respectively, are reached for a number of additional daily cycles. 38.The system of claim 36 wherein repeating at least the reducing and theincreasing the output of the at least one light source when the firstand the second real times, respectively, are reached for a number ofadditional daily cycles, further includes turning ON the at least onelight source at a time in a daily cycle that corresponds to dusk andturning OFF the at least one light source at a time in the daily cyclethat corresponds to dawn.
 39. The system of claim 21 wherein the atleast one controller further produces an external notification if thedetected level of light in the ambient environment is not within thesecond threshold of the expected level of light for the current time atthe current location.
 40. The system of claim 39 wherein when the resultof the comparison is invalid with respect to the at least one expectedcondition the at least one controller causes the output of the at leastone light source to be at least proximate a highest level of the atleast one light source.
 41. The system of claim 21, further comprising:the at least one light source.